feat: 实现微信公众号新闻和视频同步服务

- 使用 draft API 同步文章（适配个人订阅号）
- 使用 material API 同步视频（含详情获取）
- 自动建表（videos）、UPSERT 已有 articles 表
- 同步删除：微信端删除的素材自动从数据库移除
- APScheduler 定时调度，支持 --once 手动触发
- Docker + docker-compose 部署配置

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

wechat.py

@@ -0,0 +1,115 @@
+import logging
+import time
+
+import httpx
+
+import config
+
+logger = logging.getLogger(__name__)
+
+_BASE_URL = "https://api.weixin.qq.com/cgi-bin"
+
+
+class WeChatError(Exception):
+    pass
+
+
+class WeChatClient:
+    def __init__(self):
+        self._http = httpx.Client(timeout=httpx.Timeout(connect=10.0, read=30.0, write=10.0, pool=10.0))
+        self._token = None
+        self._token_expires_at = 0
+
+    def _get_access_token(self, force_refresh: bool = False):
+        if not force_refresh and self._token and time.time() < self._token_expires_at - 300:
+            return self._token
+
+        resp = self._http.post(f"{_BASE_URL}/stable_token", json={
+            "grant_type": "client_credential",
+            "appid": config.APP_ID,
+            "secret": config.APP_SECRET,
+            "force_refresh": force_refresh,
+        })
+        data = resp.json()
+        if "access_token" not in data:
+            raise WeChatError(f"Failed to get token: {data}")
+
+        self._token = data["access_token"]
+        self._token_expires_at = time.time() + data.get("expires_in", 7200)
+        logger.info("Access token refreshed")
+        return self._token
+
+    def _api_post(self, path: str, body: dict = None) -> dict:
+        token = self._get_access_token()
+        url = f"{_BASE_URL}/{path}?access_token={token}"
+        resp = self._http.post(url, json=body or {})
+        data = resp.json()
+
+        if data.get("errcode") == 40001:
+            logger.info("Token expired, force refreshing")
+            token = self._get_access_token(force_refresh=True)
+            url = f"{_BASE_URL}/{path}?access_token={token}"
+            resp = self._http.post(url, json=body or {})
+            data = resp.json()
+
+        if data.get("errcode", 0) != 0:
+            raise WeChatError(f"API error {data.get('errcode')}: {data.get('errmsg', '')}")
+
+        return data
+
+    def _api_get(self, path: str) -> dict:
+        token = self._get_access_token()
+        url = f"{_BASE_URL}/{path}?access_token={token}"
+        resp = self._http.get(url)
+        data = resp.json()
+
+        if data.get("errcode") == 40001:
+            logger.info("Token expired, force refreshing")
+            token = self._get_access_token(force_refresh=True)
+            url = f"{_BASE_URL}/{path}?access_token={token}"
+            resp = self._http.get(url)
+            data = resp.json()
+
+        if data.get("errcode", 0) != 0:
+            raise WeChatError(f"API error {data.get('errcode')}: {data.get('errmsg', '')}")
+
+        return data
+
+    def get_material_count(self) -> dict:
+        """Get total counts for each material type."""
+        return self._api_get("material/get_materialcount")
+
+    def batch_get_materials(self, material_type: str, offset: int = 0, count: int = 20) -> dict:
+        """Get a page of materials by type."""
+        return self._api_post("material/batchget_material", {
+            "type": material_type,
+            "offset": offset,
+            "count": count,
+        })
+
+    def get_material(self, media_id: str) -> dict:
+        """Get detail of a single material by media_id."""
+        return self._api_post("material/get_material", {"media_id": media_id})
+
+    def batch_get_published(self, offset: int = 0, count: int = 20, no_content: int = 0) -> dict:
+        """Get a page of published articles (freepublish, requires verified account)."""
+        return self._api_post("freepublish/batchget", {
+            "offset": offset,
+            "count": count,
+            "no_content": no_content,
+        })
+
+    def get_published_article(self, article_id: str) -> dict:
+        """Get detail of a single published article by article_id."""
+        return self._api_post("freepublish/getarticle", {"article_id": article_id})
+
+    def batch_get_drafts(self, offset: int = 0, count: int = 20, no_content: int = 0) -> dict:
+        """Get a page of draft articles."""
+        return self._api_post("draft/batchget", {
+            "offset": offset,
+            "count": count,
+            "no_content": no_content,
+        })
+
+    def close(self):
+        self._http.close()