add eth and optimism cli chainspec parser

[mattsse]

Add implementations of

reth/crates/cli/cli/src/chainspec.rs

Line 10 in d41aac3

pub trait ChainSpecParser: TypedValueParser<Value = Arc<ChainSpec>> + Default {

for ethereum and optimism

basically:

reth/crates/node/core/src/args/utils.rs

Line 45 in d41aac3

pub fn chain_value_parser(s: &str) -> eyre::Result<Arc<ChainSpec>, eyre::Error> {

but specifically for op and eth

first impl should just reuse this function as is

FYI @loocapro

[loocapro]

Up for it!