feat: Sprint 4 Phase E+F — 前端處置統計 + 週報處置分佈

Phase E: 前端頁面
- E1: /reports 完整處置統計儀表板 (已在 Sprint F 完成)
- E2: 首頁 Metrics Strip — 從 disposition API 取得真實自動化率
  優先使用 /stats/disposition auto_rate，fallback 到 incidents 推算
- E3: /auto-repair 處置概況卡片 (已在 Sprint F 完成)
- E4: /neural-command stats tab 處置分佈 (已在 Sprint F 完成)
- E5: i18n 翻譯 zh-TW + en (已在 Sprint F 完成)

Phase F: 週報 + 文件
- F1: WeeklyReportMessage 新增 disposition 5 欄位
  週報格式加「📋 處置分佈」區塊 (自動/冷啟動/人工/手動 + 自動化率)
  weekly_report_service 整合 get_all_disposition_stats()
- message 字數上限從 900 提升到 1200 (適應處置區塊)

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

apps/web/src/app/[locale]/page.tsx

@@ -365,8 +365,22 @@ export default function Home({ params }: { params: { locale: string } }) {
   // P0 count
   const p0Count = incidents?.filter(i => i.severity === 'P0').length ?? 0
 
-  // 自動處置率
+  // 2026-04-07 Claude Code: Sprint 4 E2 — 從 disposition API 取得真實自動化率
+  const [dispositionRate, setDispositionRate] = useState<{ auto_rate: number; total: number } | null>(null)
+  useEffect(() => {
+    fetch(`${API_BASE}/api/v1/stats/disposition`)
+      .then(r => r.json())
+      .then(d => {
+        if (d?.summary) setDispositionRate({ auto_rate: d.summary.auto_rate, total: d.summary.total })
+      })
+      .catch(() => {})
+  }, [])
+
+  // 自動處置率 — 優先使用 disposition API，fallback 到 incidents 推算
   const autoRemediationRate = (() => {
+    if (dispositionRate && dispositionRate.total > 0) {
+      return `${Math.round(dispositionRate.auto_rate * 100)}%`
+    }
     if (!incidents?.length) return '--'
     const resolved = incidents.filter(i => i.status === 'resolved' || i.status === 'closed').length
     return `${((resolved / incidents.length) * 100).toFixed(0)}%`
@@ -374,6 +388,9 @@ export default function Home({ params }: { params: { locale: string } }) {
 
   // 自動處置率數值 (for progress bar)
   const autoRemediationPct = (() => {
+    if (dispositionRate && dispositionRate.total > 0) {
+      return Math.round(dispositionRate.auto_rate * 100)
+    }
     if (!incidents?.length) return 0
     const resolved = incidents.filter(i => i.status === 'resolved' || i.status === 'closed').length
     return Math.round((resolved / incidents.length) * 100)