docs: Add client requirements template to default README contents (#2…

…1815)

Also updates `Client Requirements.md` to just use the template directly.
Effectively moves the source of truth for that document into
`markdown-magic`.


[AB#8577](https://dev.azure.com/fluidframework/235294da-091d-4c29-84fc-cdfc3d90890b/_workitems/edit/8577)

ClientRequirements.md

@@ -1,5 +1,10 @@
 # Platform Requirements for Fluid Framework Client Packages
 
+<!-- AUTO-GENERATED-CONTENT:START (README_CLIENT_REQUIREMENTS_SECTION:includeHeading=FALSE&headingLevel=1) -->
+
+<!-- prettier-ignore-start -->
+<!-- NOTE: This section is automatically generated using @fluid-tools/markdown-magic. Do not update these generated contents directly. -->
+
 These are the platform requirements for the current version of Fluid Framework Client Packages.
 These requirements err on the side of being too strict since within a major version they can be relaxed over time, but not made stricter.
 For Long Term Support (LTS) versions this can require supporting these platforms for several years.
@@ -41,3 +46,7 @@ Node10 resolution is not supported as it does not support Fluid Framework's API
     Once this list of workflows motivating CommonJS support is empty, we may drop support for CommonJS one year after notice of the change is posted here.
 
     -   Testing with Jest (which lacks [stable ESM support](https://jestjs.io/docs/ecmascript-modules) due to [unstable APIs in NodeJs](https://github.com/nodejs/node/issues/37648))
+
+<!-- prettier-ignore-end -->
+
+<!-- AUTO-GENERATED-CONTENT:END -->

experimental/dds/ot/ot/README.md

@@ -30,6 +30,50 @@ npm i @fluid-experimental/ot
 
 API documentation for **@fluid-experimental/ot** is available at <https://fluidframework.com/docs/apis/ot>.
 
+## Minimum Client Requirements
+
+These are the platform requirements for the current version of Fluid Framework Client Packages.
+These requirements err on the side of being too strict since within a major version they can be relaxed over time, but not made stricter.
+For Long Term Support (LTS) versions this can require supporting these platforms for several years.
+
+It is likely that other configurations will work, but they are not supported: if they stop working, we do not consider that a bug.
+If you would benefit from support for something not listed here, file an issue and the product team will evaluate your request.
+When making such a request please include if the configuration already works (and thus the request is just that it becomes officially supported), or if changes are required to get it working.
+
+### Supported Runtimes
+
+-   NodeJs ^20.10.0 except that we will drop support for it [when NodeJs 20 loses its upstream support on 2026-04-30](https://github.com/nodejs/release#release-schedule), and will support a newer LTS version of NodeJS (22) at least 1 year before 20 is end-of-life. This same policy applies to NodeJS 22 when it is end of life (2027-04-30).
+-   Modern browsers supporting the es2022 standard library: in response to asks we can add explicit support for using babel to polyfill to target specific standards or runtimes (meaning we can avoid/remove use of things that don't polyfill robustly, but otherwise target modern standards).
+
+### Supported Tools
+
+-   TypeScript 5.4:
+    -   All [`strict`](https://www.typescriptlang.org/tsconfig) options are supported.
+    -   [`strictNullChecks`](https://www.typescriptlang.org/tsconfig) is required.
+    -   [Configuration options deprecated in 5.0](https://github.com/microsoft/TypeScript/issues/51909) are not supported.
+    -   `exactOptionalPropertyTypes` is currently not fully supported.
+        If used, narrowing members of Fluid Framework types types using `in`, `Reflect.has`, `Object.hasOwn` or `Object.prototype.hasOwnProperty` should be avoided as they may incorrectly exclude `undefined` from the possible values in some cases.
+-   [webpack](https://webpack.js.org/) 5
+    -   We are not intending to be prescriptive about what bundler to use.
+        Other bundlers which can handle ES Modules should work, but webpack is the only one we actively test.
+
+### Module Resolution
+
+[`Node16`, `NodeNext`, or `Bundler`](https://www.typescriptlang.org/tsconfig#moduleResolution) resolution should be used with TypeScript compilerOptions to follow the [Node.js v12+ ESM Resolution and Loading algorithm](https://nodejs.github.io/nodejs.dev/en/api/v20/esm/#resolution-and-loading-algorithm).
+Node10 resolution is not supported as it does not support Fluid Framework's API structuring pattern that is used to distinguish stable APIs from those that are in development.
+
+### Module Formats
+
+-   ES Modules:
+    ES Modules are the preferred way to consume our client packages (including in NodeJs) and consuming our client packages from ES Modules is fully supported.
+-   CommonJs:
+    Consuming our client packages as CommonJs is supported only in NodeJS and only for the cases listed below.
+    This is done to accommodate some workflows without good ES Module support.
+    If you have a workflow you would like included in this list, file an issue.
+    Once this list of workflows motivating CommonJS support is empty, we may drop support for CommonJS one year after notice of the change is posted here.
+
+    -   Testing with Jest (which lacks [stable ESM support](https://jestjs.io/docs/ecmascript-modules) due to [unstable APIs in NodeJs](https://github.com/nodejs/node/issues/37648))
+
 ## Contribution Guidelines
 
 There are many ways to [contribute](https://github.com/microsoft/FluidFramework/blob/main/CONTRIBUTING.md) to Fluid.

experimental/framework/data-objects/README.md

@@ -32,6 +32,50 @@ npm i @fluid-experimental/data-objects
 
 API documentation for **@fluid-experimental/data-objects** is available at <https://fluidframework.com/docs/apis/data-objects>.
 
+## Minimum Client Requirements
+
+These are the platform requirements for the current version of Fluid Framework Client Packages.
+These requirements err on the side of being too strict since within a major version they can be relaxed over time, but not made stricter.
+For Long Term Support (LTS) versions this can require supporting these platforms for several years.
+
+It is likely that other configurations will work, but they are not supported: if they stop working, we do not consider that a bug.
+If you would benefit from support for something not listed here, file an issue and the product team will evaluate your request.
+When making such a request please include if the configuration already works (and thus the request is just that it becomes officially supported), or if changes are required to get it working.
+
+### Supported Runtimes
+
+-   NodeJs ^20.10.0 except that we will drop support for it [when NodeJs 20 loses its upstream support on 2026-04-30](https://github.com/nodejs/release#release-schedule), and will support a newer LTS version of NodeJS (22) at least 1 year before 20 is end-of-life. This same policy applies to NodeJS 22 when it is end of life (2027-04-30).
+-   Modern browsers supporting the es2022 standard library: in response to asks we can add explicit support for using babel to polyfill to target specific standards or runtimes (meaning we can avoid/remove use of things that don't polyfill robustly, but otherwise target modern standards).
+
+### Supported Tools
+
+-   TypeScript 5.4:
+    -   All [`strict`](https://www.typescriptlang.org/tsconfig) options are supported.
+    -   [`strictNullChecks`](https://www.typescriptlang.org/tsconfig) is required.
+    -   [Configuration options deprecated in 5.0](https://github.com/microsoft/TypeScript/issues/51909) are not supported.
+    -   `exactOptionalPropertyTypes` is currently not fully supported.
+        If used, narrowing members of Fluid Framework types types using `in`, `Reflect.has`, `Object.hasOwn` or `Object.prototype.hasOwnProperty` should be avoided as they may incorrectly exclude `undefined` from the possible values in some cases.
+-   [webpack](https://webpack.js.org/) 5
+    -   We are not intending to be prescriptive about what bundler to use.
+        Other bundlers which can handle ES Modules should work, but webpack is the only one we actively test.
+
+### Module Resolution
+
+[`Node16`, `NodeNext`, or `Bundler`](https://www.typescriptlang.org/tsconfig#moduleResolution) resolution should be used with TypeScript compilerOptions to follow the [Node.js v12+ ESM Resolution and Loading algorithm](https://nodejs.github.io/nodejs.dev/en/api/v20/esm/#resolution-and-loading-algorithm).
+Node10 resolution is not supported as it does not support Fluid Framework's API structuring pattern that is used to distinguish stable APIs from those that are in development.
+
+### Module Formats
+
+-   ES Modules:
+    ES Modules are the preferred way to consume our client packages (including in NodeJs) and consuming our client packages from ES Modules is fully supported.
+-   CommonJs:
+    Consuming our client packages as CommonJs is supported only in NodeJS and only for the cases listed below.
+    This is done to accommodate some workflows without good ES Module support.
+    If you have a workflow you would like included in this list, file an issue.
+    Once this list of workflows motivating CommonJS support is empty, we may drop support for CommonJS one year after notice of the change is posted here.
+
+    -   Testing with Jest (which lacks [stable ESM support](https://jestjs.io/docs/ecmascript-modules) due to [unstable APIs in NodeJs](https://github.com/nodejs/node/issues/37648))
+
 ## Contribution Guidelines
 
 There are many ways to [contribute](https://github.com/microsoft/FluidFramework/blob/main/CONTRIBUTING.md) to Fluid.

experimental/framework/tree-react-api/README.md

@@ -52,6 +52,50 @@ npm i @fluid-experimental/tree-react-api
 
 API documentation for **@fluid-experimental/tree-react-api** is available at <https://fluidframework.com/docs/apis/tree-react-api>.
 
+## Minimum Client Requirements
+
+These are the platform requirements for the current version of Fluid Framework Client Packages.
+These requirements err on the side of being too strict since within a major version they can be relaxed over time, but not made stricter.
+For Long Term Support (LTS) versions this can require supporting these platforms for several years.
+
+It is likely that other configurations will work, but they are not supported: if they stop working, we do not consider that a bug.
+If you would benefit from support for something not listed here, file an issue and the product team will evaluate your request.
+When making such a request please include if the configuration already works (and thus the request is just that it becomes officially supported), or if changes are required to get it working.
+
+### Supported Runtimes
+
+-   NodeJs ^20.10.0 except that we will drop support for it [when NodeJs 20 loses its upstream support on 2026-04-30](https://github.com/nodejs/release#release-schedule), and will support a newer LTS version of NodeJS (22) at least 1 year before 20 is end-of-life. This same policy applies to NodeJS 22 when it is end of life (2027-04-30).
+-   Modern browsers supporting the es2022 standard library: in response to asks we can add explicit support for using babel to polyfill to target specific standards or runtimes (meaning we can avoid/remove use of things that don't polyfill robustly, but otherwise target modern standards).
+
+### Supported Tools
+
+-   TypeScript 5.4:
+    -   All [`strict`](https://www.typescriptlang.org/tsconfig) options are supported.
+    -   [`strictNullChecks`](https://www.typescriptlang.org/tsconfig) is required.
+    -   [Configuration options deprecated in 5.0](https://github.com/microsoft/TypeScript/issues/51909) are not supported.
+    -   `exactOptionalPropertyTypes` is currently not fully supported.
+        If used, narrowing members of Fluid Framework types types using `in`, `Reflect.has`, `Object.hasOwn` or `Object.prototype.hasOwnProperty` should be avoided as they may incorrectly exclude `undefined` from the possible values in some cases.
+-   [webpack](https://webpack.js.org/) 5
+    -   We are not intending to be prescriptive about what bundler to use.
+        Other bundlers which can handle ES Modules should work, but webpack is the only one we actively test.
+
+### Module Resolution
+
+[`Node16`, `NodeNext`, or `Bundler`](https://www.typescriptlang.org/tsconfig#moduleResolution) resolution should be used with TypeScript compilerOptions to follow the [Node.js v12+ ESM Resolution and Loading algorithm](https://nodejs.github.io/nodejs.dev/en/api/v20/esm/#resolution-and-loading-algorithm).
+Node10 resolution is not supported as it does not support Fluid Framework's API structuring pattern that is used to distinguish stable APIs from those that are in development.
+
+### Module Formats
+
+-   ES Modules:
+    ES Modules are the preferred way to consume our client packages (including in NodeJs) and consuming our client packages from ES Modules is fully supported.
+-   CommonJs:
+    Consuming our client packages as CommonJs is supported only in NodeJS and only for the cases listed below.
+    This is done to accommodate some workflows without good ES Module support.
+    If you have a workflow you would like included in this list, file an issue.
+    Once this list of workflows motivating CommonJS support is empty, we may drop support for CommonJS one year after notice of the change is posted here.
+
+    -   Testing with Jest (which lacks [stable ESM support](https://jestjs.io/docs/ecmascript-modules) due to [unstable APIs in NodeJs](https://github.com/nodejs/node/issues/37648))
+
 ## Contribution Guidelines
 
 There are many ways to [contribute](https://github.com/microsoft/FluidFramework/blob/main/CONTRIBUTING.md) to Fluid.

packages/dds/cell/README.md

@@ -30,6 +30,50 @@ npm i @fluidframework/cell
 
 API documentation for **@fluidframework/cell** is available at <https://fluidframework.com/docs/apis/cell>.
 
+## Minimum Client Requirements
+
+These are the platform requirements for the current version of Fluid Framework Client Packages.
+These requirements err on the side of being too strict since within a major version they can be relaxed over time, but not made stricter.
+For Long Term Support (LTS) versions this can require supporting these platforms for several years.
+
+It is likely that other configurations will work, but they are not supported: if they stop working, we do not consider that a bug.
+If you would benefit from support for something not listed here, file an issue and the product team will evaluate your request.
+When making such a request please include if the configuration already works (and thus the request is just that it becomes officially supported), or if changes are required to get it working.
+
+### Supported Runtimes
+
+-   NodeJs ^20.10.0 except that we will drop support for it [when NodeJs 20 loses its upstream support on 2026-04-30](https://github.com/nodejs/release#release-schedule), and will support a newer LTS version of NodeJS (22) at least 1 year before 20 is end-of-life. This same policy applies to NodeJS 22 when it is end of life (2027-04-30).
+-   Modern browsers supporting the es2022 standard library: in response to asks we can add explicit support for using babel to polyfill to target specific standards or runtimes (meaning we can avoid/remove use of things that don't polyfill robustly, but otherwise target modern standards).
+
+### Supported Tools
+
+-   TypeScript 5.4:
+    -   All [`strict`](https://www.typescriptlang.org/tsconfig) options are supported.
+    -   [`strictNullChecks`](https://www.typescriptlang.org/tsconfig) is required.
+    -   [Configuration options deprecated in 5.0](https://github.com/microsoft/TypeScript/issues/51909) are not supported.
+    -   `exactOptionalPropertyTypes` is currently not fully supported.
+        If used, narrowing members of Fluid Framework types types using `in`, `Reflect.has`, `Object.hasOwn` or `Object.prototype.hasOwnProperty` should be avoided as they may incorrectly exclude `undefined` from the possible values in some cases.
+-   [webpack](https://webpack.js.org/) 5
+    -   We are not intending to be prescriptive about what bundler to use.
+        Other bundlers which can handle ES Modules should work, but webpack is the only one we actively test.
+
+### Module Resolution
+
+[`Node16`, `NodeNext`, or `Bundler`](https://www.typescriptlang.org/tsconfig#moduleResolution) resolution should be used with TypeScript compilerOptions to follow the [Node.js v12+ ESM Resolution and Loading algorithm](https://nodejs.github.io/nodejs.dev/en/api/v20/esm/#resolution-and-loading-algorithm).
+Node10 resolution is not supported as it does not support Fluid Framework's API structuring pattern that is used to distinguish stable APIs from those that are in development.
+
+### Module Formats
+
+-   ES Modules:
+    ES Modules are the preferred way to consume our client packages (including in NodeJs) and consuming our client packages from ES Modules is fully supported.
+-   CommonJs:
+    Consuming our client packages as CommonJs is supported only in NodeJS and only for the cases listed below.
+    This is done to accommodate some workflows without good ES Module support.
+    If you have a workflow you would like included in this list, file an issue.
+    Once this list of workflows motivating CommonJS support is empty, we may drop support for CommonJS one year after notice of the change is posted here.
+
+    -   Testing with Jest (which lacks [stable ESM support](https://jestjs.io/docs/ecmascript-modules) due to [unstable APIs in NodeJs](https://github.com/nodejs/node/issues/37648))
+
 ## Contribution Guidelines
 
 There are many ways to [contribute](https://github.com/microsoft/FluidFramework/blob/main/CONTRIBUTING.md) to Fluid.