docs: move completed frontend refactoring to COMPLETED.md
Moved the entire frontend refactoring section (3 phases + bug fixes)
from TODO.md to docs/archive/COMPLETED.md for better organization.
Changes:
- TODO.md: Removed completed refactoring tasks (lines 363-728)
- COMPLETED.md: Added comprehensive refactoring summary with:
- All 3 phases (Components, Hooks, Advanced Components)
- Bug fixes (formatHeat, ChatRoom missing)
- Final metrics (-559 lines, 16 new components, 3 new hooks)
- Component structure diagram
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