feat: rate limit module

[mconcat]

Description

ref: #7974 [Github]
closes: IBCGO-11 [Linear]

---

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• Targeted PR against the correct branch (see CONTRIBUTING.md).
• Linked to GitHub issue with discussion and accepted design, OR link to spec that describes this work.
• Code follows the module structure standards and Go style guide.
• Wrote unit and integration tests.
• Updated relevant documentation (docs/).
• Added relevant godoc comments.
• Provide a conventional commit message to follow the repository standards.
• Include a descriptive changelog entry when appropriate. This may be left to the discretion of the PR reviewers. (e.g. chores should be omitted from changelog)
• Re-reviewed Files changed in the GitHub PR explorer.
• Review SonarCloud Report in the comment section below once CI passes.

[codecov]

Codecov Report

Attention: Patch coverage is 56.54618% with 541 lines in your changes missing coverage. Please review.

Project coverage is 57.57%. Comparing base (2d98792) to head (3e80458).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
modules/apps/rate-limiting/client/cli/query.go	0.00%	137 Missing ⚠️
modules/apps/rate-limiting/types/msgs.go	23.38%	94 Missing and 1 partial ⚠️
modules/apps/rate-limiting/v2/ibc_middleware.go	29.26%	57 Missing and 1 partial ⚠️
modules/apps/rate-limiting/ibc_middleware.go	0.00%	51 Missing ⚠️
modules/apps/rate-limiting/module.go	0.00%	43 Missing ⚠️
modules/apps/rate-limiting/keeper/grpc_query.go	55.55%	22 Missing and 10 partials ⚠️
modules/apps/rate-limiting/keeper/packet.go	77.03%	23 Missing and 8 partials ⚠️
modules/apps/rate-limiting/types/flow.go	0.00%	24 Missing ⚠️
modules/apps/rate-limiting/client/cli/cli.go	0.00%	17 Missing ⚠️
modules/apps/rate-limiting/keeper/epoch.go	62.50%	10 Missing and 5 partials ⚠️
... and 8 more

Additional details and impacted files

@@            Coverage Diff             @@
##            main    #8268       +/-   ##
==========================================
+ Coverage   1.13%   57.57%   +56.43%     
==========================================
  Files         14      317      +303     
  Lines       2019    22673    +20654     
==========================================
+ Hits          23    13053    +13030     
- Misses      1995     9012     +7017     
- Partials       1      608      +607     

Flag	Coverage Δ
08-wasm	66.13% <ø> (?)
e2e	1.13% <0.00%> (-0.01%)	⬇️
ibc-go	62.98% <56.59%> (?)

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[linear]

IBCGO-11 Rate limiting middleware

[gjermundgaraba]

Starting to come together, but looks like we're not quite done yet :)

[gjermundgaraba]

Can you explain why this was added now, and why it worked without it in the past?

[DeshErBojhaa]

Hmm, I understand this PR may not be the best place to add this, but the reason was, I wanted to all the middleware to have similar setup style.

Something like,

RateLimit(PFM(Transfer(Chan)))

then

RateLim.ICS4(Chan)
PFM.ICS4(RateLim)
Transfer.ICS4(PFM)

But all the functionality still works if we remove this function.

[gjermundgaraba]

Let's not add it if it's not used now, it will be added in #8528

[DeshErBojhaa]

removed here 83e7ce2

[DeshErBojhaa]

Aparently this is required here https://github.com/cosmos/ibc-go/blob/feature/rate-limit/modules/apps/rate-limiting/keeper/packet_test.go#L743

So I am re introducing SetICS4Wrapper for PFM

[gjermundgaraba]

YES! Now I think we are there 💪

I'll merge this now, and after we get ibc v2 e2e tests in, I will ask @AdityaSripal to review both middlewares holistically.

[Copilot]

Pull Request Overview

This PR introduces a new rate-limiting module to the IBC-go codebase. Key changes include new middleware and keeper implementations for enforcing throughput limits on IBC transfers, comprehensive proto definitions for the rate limit APIs, and extensive unit and integration tests ensuring proper behavior.

Reviewed Changes

Copilot reviewed 63 out of 72 changed files in this pull request and generated 1 comment.

File	Description
modules/apps/rate-limiting/types/keys.go	Defines key prefixes used for storing module state; review of prefix value
modules/apps/rate-limiting/keeper/*.go	New keeper logic with repeated KV store adapter instantiation for state access

Comments suppressed due to low confidence (1)

modules/apps/rate-limiting/types/keys.go:30

• The key prefix for whitelisted addresses is set to 'address-blacklist', which appears inconsistent with its purpose. Consider renaming it to 'address-whitelist' to accurately reflect its usage.

	AddressWhitelistKeyPrefix = bytes("address-blacklist")