fix(ci): B5 整合測試 — runner 加入 compose 網路才能路由到 postgres

問題: act runner 在 Docker 容器內，compose 網路 172.30.0.x 無法直接路由
修正: docker network connect 讓 runner 加入 api_default compose 網路，
     測試後 disconnect 清理

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

.gitea/workflows/cd.yaml

@@ -133,24 +133,24 @@ jobs:
           docker compose -f docker-compose.test.yml exec -T postgres-test \
             psql -U awoooi -d awoooi_test \
             -f /dev/stdin < tests/integration/setup_test_schema.sql
-          # 取得 postgres container IP: 找 api_ 開頭的 compose 網路，取第一個有效 IP
-          # docker inspect 多網路時會拼接，用 json + jq 確保只取一個
+          # Runner 在 Docker 容器內，需加入 compose 網路才能連到 postgres-test
+          # compose 預設網路名: {project_name}_default，project = 目錄名 = api
+          COMPOSE_NETWORK=$(docker network ls --filter name=api --format '{{.Name}}' | grep default | head -1)
+          RUNNER_CONTAINER=$(hostname)
+          echo "compose network: $COMPOSE_NETWORK, runner: $RUNNER_CONTAINER"
+          if [ -n "$COMPOSE_NETWORK" ]; then
+            docker network connect "$COMPOSE_NETWORK" "$RUNNER_CONTAINER" 2>/dev/null || true
+          fi
+          # 取 postgres container IP (compose 網路內)
           CONTAINER_NAME=$(docker ps --filter name=postgres-test --format '{{.Names}}' | head -1)
-          echo "postgres-test container: $CONTAINER_NAME"
           PG_IP=$(docker inspect "$CONTAINER_NAME" \
             --format '{{json .NetworkSettings.Networks}}' \
             | python3 -c "import sys,json; nets=json.load(sys.stdin); print(list(nets.values())[0]['IPAddress'])" 2>/dev/null)
-          # fallback: host 上 exposed port 15432
-          if [ -z "$PG_IP" ]; then
-            PG_IP="127.0.0.1"
-            PG_PORT="15432"
-          else
-            PG_PORT="5432"
-          fi
-          echo "postgres-test IP: $PG_IP:$PG_PORT"
-          TEST_DATABASE_URL="postgresql+asyncpg://awoooi:awoooi_test_2026@${PG_IP}:${PG_PORT}/awoooi_test?ssl=disable" \
+          echo "postgres-test: $CONTAINER_NAME @ $PG_IP:5432"
+          TEST_DATABASE_URL="postgresql+asyncpg://awoooi:awoooi_test_2026@${PG_IP}:5432/awoooi_test?ssl=disable" \
             /opt/api-venv/bin/pytest tests/integration/test_b5_core_flows.py -v --tb=short
           TEST_EXIT=$?
+          docker network disconnect "$COMPOSE_NETWORK" "$RUNNER_CONTAINER" 2>/dev/null || true
           docker compose -f docker-compose.test.yml down -v 2>/dev/null || true
           exit $TEST_EXIT