Change counterpartyInfo to channel

[AdityaSripal]

Description

This PR renames counterpartyInfo to channel

Moreover it does not assume that the counterpartyId is necessarily a clientID. I think here the logic looks much more in-line with IBC-go and hopefully will do a lot to remove the confusions raised in the referenced spec issue.

For now, I have a single contract implementing ICS02 and ICS04 specs since ICS04 doesn't have too many additional functions. I can rename the file to CoreRouter to make this clearer rather than ICS02Client.

TODO:

• Rename ICS02Client to something that indicates it is doing both ICS02 client and ICS04 channel
• Fix e2e tests

ref: cosmos/ibc#1164

---

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[srdtrk]

Good start. I still feel like it was easier to wrap your head around when it was called counterparty info. If we were explaining this to a 3rd party, the first one sounds simpler imo:

• Each light client has a counterparty chain info associated with it.
• Each light client has a channel associated with it that carries some counterparty info where channelId equals clientId.

But if we need to do this to follow spec then I won't block it. There are a couple more things to do before we can merge this:

• Fix linting issues (just lint)
• Have foundry tests all pass and codecov increase. (just test-foundry)
• Regenerate abi (Probably generate-abi recepe in the justfile needs to be updated due to contract name change)
• Update e2e tests
• Update benchmarks

We can take care of the last three after you take the first two?

[srdtrk]

CounterpartyInfo feels more descriptive ngl 😅. Because the same light client cannot have multiple channels on top in our implementation I think

[srdtrk]

The link should be updated?

[codecov]

Codecov Report

Attention: Patch coverage is 95.45455% with 1 line in your changes missing coverage. Please review.

Project coverage is 96.84%. Comparing base (169400e) to head (21d7beb).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
contracts/ICS26Router.sol	91.66%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #100      +/-   ##
==========================================
+ Coverage   95.33%   96.84%   +1.51%     
==========================================
  Files          11       11              
  Lines         450      539      +89     
==========================================
+ Hits          429      522      +93     
+ Misses         21       17       -4     

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