feat: use different gas pricing api to replace gasnow

[sambacha]

Change Gas Pricing API Endpoint

this closes #24

• utilizes api.txprice.com
• fixes some shell formatting and permissions
• all prices are denominated in nanoeth (gwei)

{
	"system": "ethereum",
	"network": "main",
	"unit": "gwei",
	"maxPrice": 123,
	"currentBlockNumber": 13005095,
	"msSinceLastBlock": 3793,
	"blockPrices": [{
    "blockNumber": 13005096,
    "baseFeePerGas": 94.647990462,
    "estimatedTransactionCount": 137,
      "estimatedPrices": [              // json.blockPrices[0].estimatedPrices[0] 
        {
          "confidence": 99,             // json.blockPrices[0].estimatedPrices[0].confidence
          "price": 104,                 // json.blockPrices[0].estimatedPrices[0].price
          "maxPriorityFeePerGas": 9.86, // json.blockPrices[0].estimatedPrices[0].maxFeePerGas
          "maxFeePerGas": 199.16        // json.blockPrices[0].estimatedPrices[0].maxFeePerGas 
        }
    ]
}]
}

Additional available data points

.blockPrices[0].baseFeePerGas = 95.787159441;
.blockPrices[0].blockNumber = 13146395;
.currentBlockNumber = 13146394;
.maxPrice = 275;
.msSinceLastBlock = 70024;
.blockPrices[0].estimatedPrices[0].maxFeePerGas 
blockPrices[0].estimatedPrices[0].maxFeePerGas
blockPrices[0].estimatedPrices[0].price
blockPrices[0].estimatedPrices[0].confidence // 99,95,90,80,70
blockPrices[0].estimatedPrices

Confidence Interval

confidence is defined as the, "

0-99 likelihood the next block will contain a transaction with a gas price >= to the listed price

I can override the default confidence level order response (99,95,90,80,70) with a response of up to 5 confidence levels from 1 - 99 if yall think it would be more useful. I can provide this as a separate api endpoint (e.g. dapptools.txprice.com or w/e).

Signed-off-by: sam bacha sam@manifoldfinance.com

[gakonst]

@mds1 @transmissions11 wdyt about using the above provider?

[mds1]

Yea I like blocknative's estimates, and this one is just a proxy to blocknative, so good with me

[mds1]

Blocknative docs say "Order of confidence intervals is subject to change", so we might want to be a little smarter about finding the confidence value in the array instead of assuming the order. This is probably ok for now though and we could create an issue to handle it better in the future. Will defer to @gakonst here

[sambacha]

as an alternative, you can use https://etherchain.org/api/gasnow @gakonst if you prefer to use a miner provided API

[gakonst]

Yeah I'm OK with that - thank you! We can reconsider if it ends up not working well enough.