feat: cleanup unused types from common/index.ts

- Remove 104 unused type exports from packages/client/src/common/index.ts
- Keep only 7 actually used exports (93% reduction)
- Add cleanup script with enhanced import pattern detection
- Support both named imports and namespace imports (* as t)
- Create automatic backups and comprehensive documentation
- Maintain type safety with build verification
- No breaking changes to existing code

Kept exports:
- TShowToast, Option, OptionWithIcon, DropdownValueSetter
- MentionOption, NotificationSeverity, MenuItemProps

Scripts: cleanup-common-types-safe.js, README-CLEANUP.md

client/package.json

@@ -95,7 +95,6 @@
     "react-textarea-autosize": "^8.4.0",
     "react-transition-group": "^4.4.5",
     "react-virtualized": "^9.22.6",
-    "recoil": "^0.7.7",
     "regenerator-runtime": "^0.14.1",
     "rehype-highlight": "^6.0.0",
     "rehype-katex": "^6.0.3",