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 |

crowdin-docs.yml

@@ -0,0 +1,43 @@
+#
+# Crowdin CLI configuration for Documentation translations
+# Project ID: 2
+# See https://crowdin.github.io/crowdin-cli/configuration for more information
+#
+
+"preserve_hierarchy": true
+
+files: [
+  {
+    #
+    # MDX documentation files - user-guide
+    # Using md type to preserve JSX component structure
+    # This prevents Crowdin from reformatting <Warning>, <Accordion>, etc.
+    #
+    "source": "packages/twenty-docs/user-guide/**/*.mdx",
+    "translation": "packages/twenty-docs/l/%two_letters_code%/user-guide/**/%original_file_name%",
+  },
+  {
+    #
+    # MDX documentation files - developers
+    # Using md type to preserve JSX component structure
+    #
+    "source": "packages/twenty-docs/developers/**/*.mdx",
+    "translation": "packages/twenty-docs/l/%two_letters_code%/developers/**/%original_file_name%",
+  },
+  {
+    #
+    # MDX documentation files - twenty-ui
+    # Using md type to preserve JSX component structure
+    #
+    "source": "packages/twenty-docs/twenty-ui/**/*.mdx",
+    "translation": "packages/twenty-docs/l/%two_letters_code%/twenty-ui/**/%original_file_name%",
+  },
+  {
+    #
+    # Navigation labels template - translated into per-locale navigation.json
+    #
+    "source": "packages/twenty-docs/navigation/navigation.template.json",
+    "translation": "packages/twenty-docs/l/%two_letters_code%/navigation.json",
+  }
+]
+