feat: complete i18n translation for remaining components

- Translate pages: Projects, ProjectHealthPage, ProjectSettings
- Translate components: TaskDetailModal, KanbanBoard, Comments,
  SubtaskList, CalendarView, BlockerDialog
- Add translation keys for tasks namespace: kanban, calendar,
  subtasks.error, comments.error, blockers (full translation)
- Add common.labels.task translation key
- Fix task creation: use original_estimate instead of time_estimate

Translation coverage:
- 10 locale files updated (zh-TW & en)
- 6 page/component files translated
- ~100 new translation keys added

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

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

frontend/public/locales/zh-TW/health.json

@@ -1,12 +1,29 @@
 {
-  "title": "專案健康度",
-  "subtitle": "監控專案的整體健康狀況",
+  "title": "專案健康度儀表板",
+  "subtitle": "監控所有專案的健康狀況與風險等級",
   "overall": {
     "title": "整體健康度",
     "healthy": "健康",
     "atRisk": "風險中",
     "critical": "危急"
   },
+  "summary": {
+    "totalProjects": "專案總數",
+    "healthy": "健康",
+    "atRisk": "風險中",
+    "critical": "危急",
+    "avgHealth": "平均健康度",
+    "withBlockers": "有阻擋問題",
+    "delayed": "延遲"
+  },
+  "sort": {
+    "label": "排序方式",
+    "riskHigh": "風險：高到低",
+    "riskLow": "風險：低到高",
+    "healthHigh": "健康度：高到低",
+    "healthLow": "健康度：低到高",
+    "name": "名稱：A 到 Z"
+  },
   "metrics": {
     "schedule": "進度",
     "budget": "預算",
@@ -34,15 +51,21 @@
     "high": "高風險",
     "medium": "中風險",
     "low": "低風險",
+    "critical": "危急",
     "mitigated": "已緩解"
   },
   "actions": {
     "viewDetails": "查看詳情",
     "exportReport": "匯出報告",
-    "setAlert": "設定警示"
+    "setAlert": "設定警示",
+    "retry": "重試"
   },
+  "projectCount": "{{count}} 個專案",
   "empty": {
-    "title": "沒有健康度資料",
-    "description": "專案需要更多資料才能顯示健康度指標"
+    "title": "沒有專案",
+    "description": "建立專案以開始追蹤健康狀態"
+  },
+  "error": {
+    "loadFailed": "載入專案健康度資料失敗，請重試。"
   }
 }