test(social): add unit tests for useOptimisticLike and useOptimisticRepost

[DSanich]

Summary

• Add src/hooks/useOptimisticLike.test.ts covering optimistic video-social-metrics / video-user-interactions updates, kind 5 delete when unliking with a stored like event id, kind 7 like publish with e / a / p tags (including vineId: null address form), skip publish when unliking without an event id, likeCount floored at 0 on unlike, and rollback + destructive toast when publishEvent fails (like and unlike paths).
• Add src/hooks/useOptimisticRepost.test.ts covering kind 5 un-repost, repostVideo arguments and returned repostEventId, skip publish when removing repost without an event id, repostCount floored at 0, and rollback when repostVideo or kind 5 delete fails.

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

• useOptimisticLike and useOptimisticRepost power high-traffic social UI but had no colocated tests; components only mocked these hooks, so cache keys, optimistic deltas, Nostr publish calls, and error rollback were easy to regress silently.

Related Issue

• Closes test(social): unit tests for useOptimisticLike and useOptimisticRepost #340

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://054c6c4c.divine-web-fm8.pages.dev
Commit	2ad2387
Branch	test/340-optimistic-like-repost