feat(i18n): fix translation QA issues and add automation (#16756)

## Summary

This PR fixes translation QA issues and adds automation to prevent
future issues.

### Translation Fixes
- Fixed **escaped Unicode sequences** in translations (e.g.,
`\u62db\u5f85` → `招待`)
- Removed **corrupted control characters** from .po files (null bytes,
invalid characters)
- Fixed **missing/incorrect placeholders** in various languages
- Deleted **35 problematic translations** via Crowdin API that had
variable mismatches

### New Scripts (in `packages/twenty-utils/`)
- `fix-crowdin-translations.ts` - Auto-fixes encoding issues and syncs
to Crowdin
- `fix-qa-issues.ts` - Fixes specific QA issues via Crowdin API
- `translation-qa-report.ts` - Generates weekly QA report from Crowdin
API

### New Workflow
- `i18n-qa-report.yaml` - Weekly workflow that creates a PR with
translation QA issues for review

### Other Changes
- Moved GitHub Actions from `.github/workflows/actions/` to
`.github/actions/`
- Fixed `date-utils.ts` to avoid nested `t` macros in plural expressions
(root cause of confusing placeholders)

### QA Status After Fixes
| Category | Count | Status |
|----------|-------|--------|
| variables | 0 ✅ | Fixed |
| tags | 1 | Minor |
| empty | 0 ✅ | Fixed |
| spaces | 127 | Low priority |
| numbers | 246 | Locale-specific |
| special_symbols | 268 | Locale-specific |

.github/workflows/ci-docs.yaml

@@ -40,7 +40,7 @@ jobs:
           fetch-depth: 0
 
       - name: Install dependencies
-        uses: ./.github/workflows/actions/yarn-install
+        uses: ./.github/actions/yarn-install
 
       - name: Docs / Lint English MDX files
         run: npx eslint "packages/twenty-docs/{developers,user-guide,twenty-ui,getting-started,snippets}/**/*.mdx" --max-warnings 0