feat: add a --dev option

[pistomat]

Implements features described in #3699, adds the following cli arguments:

Dev testnet:
      --dev
          Start the node in dev mode
          
          This mode uses a local proof-of-authority consensus engine with either fixed block times
          or automatically mined blocks.
          Disables network discovery and enables local http server.
          Prefunds 20 accounts derived by mnemonic "test test test test test test test test test test
          test junk" with 10 000 ETH each.

      --dev.block_max_transactions <BLOCK_MAX_TRANSACTIONS>
          How many block_max_transactions to mine per block

      --dev.block_time <BLOCK_TIME>
          Interval between blocks

This configuration enables developers to experiment with Reth's source code or develop new applications without having to sync to a pre-existing public network.

[onbjerg]

Will take a look, currently having some issues with CI, so it will take a minute. Sorry for the delayed review

[mattsse]

supportive, smol nit re docs.

otherwise this looks pretty good

[mattsse]

these should be mutually exclusive, but I can see how this would be more convenient coming from CLI

so at the very least, this needs to be included in the docs

[pistomat]

I was not sure how to handle this. Throw if both are Some? Merge them to one enum parameter including both variants?

[onbjerg]

also lgtm w mattse's review - please open up an issue about including this in the book (new flags, we should also document what accounts are funded)

[codecov]

Codecov Report

Merging #3866 (570e273) into main (39cd0e0) will increase coverage by 0.29%.
The diff coverage is 85.12%.

Files Changed	Coverage Δ
bin/reth/src/args/network_args.rs	15.27% <ø> (ø)
bin/reth/src/args/rpc_server_args.rs	51.26% <ø> (ø)
crates/consensus/auto-seal/src/lib.rs	0.00% <0.00%> (ø)
crates/primitives/src/constants.rs	100.00% <ø> (ø)
crates/primitives/src/lib.rs	100.00% <ø> (ø)
bin/reth/src/args/utils.rs	74.64% <50.00%> (-0.72%)	⬇️
bin/reth/src/node/mod.rs	11.99% <57.14%> (+1.92%)	⬆️
bin/reth/src/args/dev_args.rs	93.18% <93.18%> (ø)
crates/primitives/src/chain/mod.rs	95.23% <100.00%> (+0.06%)	⬆️
crates/primitives/src/chain/spec.rs	97.70% <100.00%> (+0.08%)	⬆️

... and 43 files with indirect coverage changes

Flag	Coverage Δ
integration-tests	15.51% <0.00%> (-0.05%)	⬇️
unit-tests	64.44% <85.12%> (+0.31%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Components	Coverage Δ
reth binary	27.24% <78.37%> (+0.76%)	⬆️
blockchain tree	83.01% <ø> (-0.02%)	⬇️
pipeline	89.66% <ø> (+0.06%)	⬆️
storage (db)	74.19% <ø> (-0.07%)	⬇️
trie	94.70% <ø> (+0.05%)	⬆️
txpool	46.00% <ø> (-0.58%)	⬇️
networking	77.66% <ø> (-0.05%)	⬇️
rpc	58.25% <ø> (+0.74%)	⬆️
consensus	64.46% <0.00%> (-0.83%)	⬇️
revm	33.68% <ø> (ø)
payload builder	6.61% <ø> (ø)
primitives	88.06% <100.00%> (-0.02%)	⬇️

[mattsse]

this is the best solution imo, even if it makes calling it slightly more verbose