fix: 修復 3 個 P0 Bug

1. E2E Health: Docker 容器無法訪問內網 IP，改用公網域名
2. metrics_repository: asyncpg 需要 datetime 物件，不能用字串
3. metrics_repository: PostgreSQL 用 date_trunc 而非 strftime

2026-03-31 ogt: 首席架構師審查發現並修復

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

.gitea/workflows/e2e-health.yaml

@@ -24,8 +24,8 @@ jobs:
         id: health_check
         run: |
           sudo apt-get update && sudo apt-get install -y curl || (apt-get update && apt-get install -y curl)
-          # 使用 host.docker.internal 或直接 IP
-          API_URL="http://192.168.0.121:32334"
+          # 2026-03-31 ogt: Docker 容器無法訪問內網 IP，改用公網域名
+          API_URL="https://awoooi.wooo.work"
           echo "🔗 檢查 API 健康狀態..."
 
           for i in 1 2 3; do

apps/api/src/repositories/metrics_repository.py

@@ -56,8 +56,8 @@ class MetricsDBRepository(IMetricsRepository):
         """
         try:
             async with get_db_context() as session:
+                # 2026-03-31 ogt: asyncpg 需要 datetime 物件，不能用字串
                 cutoff = datetime.now(UTC) - timedelta(hours=hours)
-                cutoff_str = cutoff.isoformat()
 
                 # Query: 統計 executed vs total (approved + executed + execution_failed)
                 query = text("""
@@ -69,7 +69,7 @@ class MetricsDBRepository(IMetricsRepository):
                     AND status IN ('approved', 'executed', 'execution_failed')
                 """)
 
-                result = await session.execute(query, {"cutoff": cutoff_str})
+                result = await session.execute(query, {"cutoff": cutoff})
                 row = result.fetchone()
 
                 if row and row.total_count > 0:
@@ -119,13 +119,14 @@ class MetricsDBRepository(IMetricsRepository):
         """
         try:
             async with get_db_context() as session:
+                # 2026-03-31 ogt: asyncpg 需要 datetime 物件，不能用字串
                 cutoff = datetime.now(UTC) - timedelta(hours=hours)
-                cutoff_str = cutoff.isoformat()
 
                 # Trend: 過去 N 個時間點的成功率 (每小時一點)
+                # 2026-03-31 ogt: PostgreSQL 用 date_trunc 而非 strftime
                 trend_query = text("""
                     SELECT
-                        strftime('%Y-%m-%d %H:00:00', created_at) as hour_bucket,
+                        date_trunc('hour', created_at) as hour_bucket,
                         COUNT(CASE WHEN status = 'executed' THEN 1 END) * 100.0 /
                         NULLIF(COUNT(*), 0) as hourly_rate
                     FROM approval_records
@@ -138,7 +139,7 @@ class MetricsDBRepository(IMetricsRepository):
 
                 result = await session.execute(
                     trend_query,
-                    {"cutoff": cutoff_str, "limit": points},
+                    {"cutoff": cutoff, "limit": points},
                 )
                 rows = result.fetchall()