fix message hasher and tests

[makramkd]

Motivation

Fix the message hasher EVM implementation after the chainlink-common and chainlink-ccip bumps which alter the Message type.

Solution

[github-actions]

LCOV of commit 5cc7fca during Solidity Foundry #6322

Summary coverage rate:
  lines......: 98.7% (1830 of 1855 lines)
  functions..: 96.3% (340 of 353 functions)
  branches...: 90.4% (756 of 836 branches)

Files changed coverage rate: n/a

[elatoskinas]

suggestion: once we support more chains, might be easier to just create a map bytes -> string and just lookup the value. We could maintain that constants file in the same file as we would do chain selector family lookups

[makramkd]

Yeah, thats a good point. I think there's quite a bit of room for improvement in terms of code organization (and possibly these interfaces) after we get the basic functionality working.

[makramkd]

The order of operations for parsing the extra args would be something like:

• Look up the chain family for the source chain and dest chain selectors
• Decode the extra args with the chain-family specific extra args decoder, return the decoded values for the dest chain
  • Within each extra args decoder, you'd have some kind of table, for EVM we'd have a table of valid tags, for others we'd probably want to follow a similar pattern.