Fix create PR gh helper i18n (vibe-kanban) (#1290)

* Perfect! I've successfully fixed all i18n issues for the Create PR GitHub helper. Here's a summary of what was completed:

## Summary

All i18n issues have been resolved! The `check-i18n.sh` script now passes with flying colors.

### Changes Made:

1. **Added translation keys to tasks.json** (all 4 languages: en, ja, ko, es):
   - `createPrDialog.title`: "Create GitHub Pull Request"
   - `createPrDialog.description`: Dialog description
   - `createPrDialog.titleLabel`, `titlePlaceholder`: PR title field
   - `createPrDialog.descriptionLabel`, `descriptionPlaceholder`: PR description field
   - `createPrDialog.baseBranchLabel`: Base branch selector
   - `createPrDialog.loadingBranches`, `selectBaseBranch`: Branch loading states
   - `createPrDialog.creating`, `createButton`: Submit button states
   - `createPrDialog.errors.*`: All error messages (insufficientPermissions, repoNotFoundOrNoAccess, failedToCreate)

2. **Updated CreatePRDialog.tsx**:
   - Changed `useTranslation()` to `useTranslation('tasks')` to specify namespace
   - Replaced all 14 hardcoded strings with `t('createPrDialog.*')` translation calls
   - Used `t('common:buttons.cancel')` for the cancel button

3. **Added integrations.github.cliSetup keys to settings.json** (all 4 languages):
   - Created new `integrations` namespace at root level
   - Added all GitHub CLI setup keys that were previously only in `settings.general.github`
   - This ensures the keys exist at both paths for backward compatibility

### Test Results:

✅ **No new literal strings introduced** - Actually removed 6 hardcoded strings!
✅ **No duplicate JSON keys found**
✅ **Translation keys are consistent across all locales** (en, ja, ko, es)

The implementation properly handles all error cases, dialog fields, and button states with proper i18n support across all 4 supported languages.

* Cleanup script changes for task attempt 30cf60d2-f2bc-443a-9c72-28b94962f155

frontend/src/i18n/locales/ja/tasks.json

@@ -103,6 +103,22 @@
     "closeButton": "閉じる"
   },
   "createPrDialog": {
+    "title": "GitHub プルリクエストを作成",
+    "description": "このタスク試行のプルリクエストをGitHubで作成します。",
+    "titleLabel": "タイトル",
+    "titlePlaceholder": "PRタイトルを入力",
+    "descriptionLabel": "説明 (オプション)",
+    "descriptionPlaceholder": "PR説明を入力",
+    "baseBranchLabel": "ベースブランチ",
+    "loadingBranches": "ブランチを読み込み中...",
+    "selectBaseBranch": "ベースブランチを選択",
+    "creating": "作成中...",
+    "createButton": "PRを作成",
+    "errors": {
+      "insufficientPermissions": "権限が不足しています。GitHub CLIに必要な権限があることを確認してください。",
+      "repoNotFoundOrNoAccess": "リポジトリが見つからないか、アクセス権がありません。リポジトリへのアクセス権を確認し、認証されていることを確認してください。",
+      "failedToCreate": "GitHub PRの作成に失敗しました"
+    },
     "loginRequired": {
       "title": "プルリクエストを作成するにはサインインしてください",
       "description": "このタスクでプルリクエストを開く前にサインインが必要です。サインインページに移動します。",