fix(honcho): 容器端口必须用容器内端口，不能用 host 映射端口

vm61 honcho-api 一直 unhealthy + deriver 反复重启，根因是 stack.yml 把
宿主机映射端口 (HONCHO_DB_PORT=25432) 当成了容器间互访端口：
- DB_CONNECTION_URI 里 database:${HONCHO_DB_PORT} 应为 database:5432
- healthcheck URL localhost:18000 应为 localhost:8000
HONCHO_API_PORT/DB_PORT/REDIS_PORT 仅用于宿主机 ports 映射段，
容器之间互访必须硬编码容器内端口 (5432/6379/8000)。

- 改 stack.yml api + deriver 段 DB_CONNECTION_URI 端口为 5432
- 改 stack.yml api 段 healthcheck URL 为 localhost:8000
- readme 关键陷阱加第 6 条："容器端口 vs 宿主机端口不可混用"
- vm61 4 honcho 容器全部 healthy，deriver queue processor 已正常运行

honcho/stack.yml

@@ -35,7 +35,7 @@ services:
       - "${HONCHO_API_PORT:-8000}:8000"
     environment:
       - TZ=Asia/Shanghai
-      - DB_CONNECTION_URI=postgresql+psycopg://${HONCHO_DB_USER}:${HONCHO_DB_PASSWORD}@database:${HONCHO_DB_PORT}/${HONCHO_DB_NAME}
+      - DB_CONNECTION_URI=postgresql+psycopg://${HONCHO_DB_USER}:${HONCHO_DB_PASSWORD}@database:5432/${HONCHO_DB_NAME}
       - CACHE_URL=redis://redis:${HONCHO_REDIS_PORT}/0?suppress=true
       - CACHE_ENABLED=true
       - LOG_LEVEL=${HONCHO_LOG_LEVEL:-INFO}
@@ -64,7 +64,7 @@ services:
         - CMD
         - /app/.venv/bin/python
         - -c
-        - "import urllib.request; urllib.request.urlopen('http://localhost:18000/health', timeout=2).read()"
+        - "import urllib.request; urllib.request.urlopen('http://localhost:8000/health', timeout=2).read()"
       interval: 10s
       timeout: 5s
       retries: 10
@@ -88,7 +88,7 @@ services:
         condition: service_healthy
     environment:
       - TZ=Asia/Shanghai
-      - DB_CONNECTION_URI=postgresql+psycopg://${HONCHO_DB_USER}:${HONCHO_DB_PASSWORD}@database:${HONCHO_DB_PORT}/${HONCHO_DB_NAME}
+      - DB_CONNECTION_URI=postgresql+psycopg://${HONCHO_DB_USER}:${HONCHO_DB_PASSWORD}@database:5432/${HONCHO_DB_NAME}
       - CACHE_URL=redis://redis:${HONCHO_REDIS_PORT}/0?suppress=true
       - CACHE_ENABLED=true
       - NAMESPACE=${HONCHO_NAMESPACE:-honcho}