fix: resolve telegram auth token expiration and clean up codebase

- Fix stale initData comparison in clearStaleSessionIfNeeded that destroyed
  valid refresh tokens on mobile WebView reopens
- Restrict X-Telegram-Init-Data header to auth endpoints only
- Close Mini App on auth retry to force fresh initData from Telegram
- Merge Connection page error/not-configured states for better UX
- Remove unnecessary comments across 40+ files (section dividers,
  restating comments, noise catch block comments)
- Configure ESLint allowEmptyCatch to properly handle intentional
  empty catch blocks (62 warnings resolved)

eslint.config.js

@@ -31,7 +31,7 @@ export default tseslint.config(
       'react-refresh/only-export-components': ['warn', { allowConstantExport: true }],
       '@typescript-eslint/no-explicit-any': 'warn',
       '@typescript-eslint/no-unused-vars': ['warn', { argsIgnorePattern: '^_' }],
-      'no-empty': 'warn',
+      'no-empty': ['warn', { allowEmptyCatch: true }],
       'no-eval': 'error',
       'no-implied-eval': 'error',
       'no-new-func': 'error',