feat: show LLM review results on bounty detail

[RYB-404]

Summary

• Add an LLM review results panel to bounty detail pages for Claude, Codex, and Gemini
• Show side-by-side score, quality indicator, confidence percentage, summary, suggested improvements, and full reasoning links
• Extend the bounty type with optional API-provided llm_reviews, while providing deterministic fallback reviews until backend data is available
• Add focused Vitest coverage for fallback and API-provided review rendering

Verification

• npm test -- llm-review-panel.test.tsx
• npm run build was attempted, but the current frontend build fails before this change because multiple existing files import missing lib/animations and lib/utils modules.

Closes #837

[RYB-404]

Solana/FNDRY payout wallet: 3Q4NGMeZftuULSmAB8ziqT2DYBfwzkqAYTng8SDrBnox