docs(hooks): add doc comments to all public types

[HUQIANTAO]

Add doc comments to all public types in the hooks crate: HookEvent, HookSink trait, StdoutHookSink, JsonlHookSink, WebhookHookSink, UnixSocketHookSink, and HookDispatcher.

Greptile Summary

The review has been completed and submitted via the greptile-review tools. One P2 documentation inaccuracy was found in the HookSink trait doc where it claims errors are "logged" when they are actually silently discarded by HookDispatcher::emit.

Confidence Score: 4/5

Safe to merge; the change is documentation-only and does not touch any runtime logic.

All comments are accurate except for one sentence in the HookSink trait doc that says errors are logged when they are actually silently discarded by HookDispatcher::emit.

crates/hooks/src/lib.rs around lines 98-101 in the HookSink trait doc.

_{Reviews (1): Last reviewed commit: "docs(hooks): add doc comments to all pub..." | Re-trigger Greptile}

[gemini-code-assist]

Warning

You have reached your daily quota limit. Please wait up to 24 hours and I will start processing your requests again!

[greptile-apps]

HUQIANTAO has reached the 50-review limit for trial accounts. To continue receiving code reviews, upgrade your plan.

[Hmbown]

Thanks for filling in the hooks docs. I pushed a tiny maintainer follow-up to make the HookSink error-handling wording match the current dispatcher behavior: sink errors are discarded so hooks stay best-effort. Local checks passed in the PR worktree: cargo fmt --all --check, cargo test -p codewhale-hooks --all-features --locked, and git diff --check.