Fix comprehensive lint and type errors across codebase

- Replace explicit 'any' types with 'unknown' or specific types
- Fix Jest DOM test setup with proper type definitions
- Resolve NODE_ENV assignment errors using Object.defineProperty
- Fix React Hook dependency warnings with useCallback patterns
- Remove unused variables and add appropriate ESLint disables
- Update documentation with groups feature information
- Ensure all tests pass with proper TypeScript compliance

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

tsconfig.json

@@ -24,6 +24,6 @@
       "@/*": ["./*"]
     }
   },
-  "include": ["next-env.d.ts", "**/*.ts", "**/*.tsx", ".next/types/**/*.ts", "lib/obsService.js"],
+  "include": ["next-env.d.ts", "**/*.ts", "**/*.tsx", ".next/types/**/*.ts", "lib/obsService.js", "types/**/*.d.ts"],
   "exclude": ["node_modules"]
 }