refactor(docker): merge two-container setup into single container (#657)

* refactor(docker): merge two-container setup into single container

The Web UI already manages the Hermes Agent gateway lifecycle internally
via GatewayManager (spawn hermes gateway run --replace), making the
separate hermes-agent container redundant. The Dockerfile is built on
the hermes-agent base image, so all CLI tooling is already included.

- Remove hermes-agent service and shared volume from docker-compose.yml
- Remove gateway port mapping (8642-8670) — internal-only now
- Update docs/docker.md, README.md, README_zh.md for single-container setup

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

* docs: remove version tag from image references

Use ekkoye8888/hermes-web-ui instead of ekkoye8888/hermes-web-ui:latest
to avoid pinning a specific version in documentation.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.7 <noreply@anthropic.com>

README_zh.md

@@ -192,14 +192,14 @@ hermes-web-ui start
 
 ### Docker Compose
 
-使用仓库内置的 compose 文件联合运行 Hermes Agent + Web UI：
+单容器部署，内置 Hermes Agent 运行时：
 
 ```bash
 # 使用预构建镜像（推荐）
-WEBUI_IMAGE=ekkoye8888/hermes-web-ui:latest docker compose up -d hermes-agent hermes-webui
+WEBUI_IMAGE=ekkoye8888/hermes-web-ui docker compose up -d
 
 # 或从源码构建
-docker compose up -d --build hermes-agent hermes-webui
+docker compose up -d --build
 
 docker compose logs -f hermes-webui
 ```