test(comments): extract NIP-22 tag builder and add usePostComment tests

[DSanich]

Summary

• Extract buildNip22CommentTags(root, reply?) into src/lib/buildNip22CommentTags.ts — pure NIP-22 (kind 1111) tag construction previously inlined in usePostComment (URL vs event roots, addressable/replaceable/regular kinds, reply vs top-level branches).
• Wire usePostComment to call the helper inside mutationFn so publish payloads stay identical while logic becomes unit-testable.
• Add buildNip22CommentTags.test.ts with fixtures for addressable short-video roots (kind 34236), regular/replaceable roots, URL roots, threaded replies (including reply-as-URL).
• Add usePostComment.test.ts with mocked useNostrPublish / useCurrentUser: asserts publishEvent receives kind: 1111 and matching tags (including reply); exercises cancelQueries, deferred-publish optimistic UI, onSuccess replacement + invalidateQueries after the 6s delay (fake timers), and onError rollback.

Avoid naming corporate partners, customers, or other sensitive external brands in this PR title or body. Use generic descriptors unless a maintainer explicitly approves the public reference.

Motivation

• Comment tag matrices are easy to get wrong; mistakes surface as missing threads or indexer mismatches rather than obvious UI errors. test(comments): unit tests for NIP-22 comment tags and usePostComment #341 asks for extracted, tested tag construction plus hook coverage for cache/publishEvent behaviour.

Related Issue

• Closes test(comments): unit tests for NIP-22 comment tags and usePostComment #341

Testing

• npm run test
• Manual verification completed

Visuals

• UI change with screenshots/video attached
• No visual change
• Visuals and text avoid sensitive external brand or partner names unless explicitly approved

[github-actions]

🚀 Preview Deployment

Property	Value
Preview URL	https://d3dedf75.divine-web-fm8.pages.dev
Commit	eb1676c
Branch	test/341-nip22-post-comment

[jalcine]

Is there an issue that this is in relation to? If not, I suggest opening one so we can discuss the merit of this. This is in lieu of the contributing guidelines.

EDIT: I see it, going to review that