Add Jin10 QR connection with cancellable login tasks

Store account credentials encrypted and bind QR tasks to administrator sessions. Report calendar access as awaiting validation after login.

Prevent late polls and status responses from overwriting cancelled or newer operations, and clean up QR tasks when settings unmount. Cover authentication, cancellation races, and stale frontend responses.

backend/src/alphapulse/calendar/jin10_auth.py

@@ -0,0 +1,66 @@
+"""Use the QR endpoints published by Jin10's current login component."""
+import base64
+from io import BytesIO
+
+import httpx
+import qrcode
+
+UC_URL = "https://uc-api.jin10.com"
+HEADERS = {"User-Agent": "Mozilla/5.0", "Referer": "https://rili.jin10.com/",
+           "x-app-id": "YDcStOzjliuTJUvh", "x-version": "1.0.0"}
+
+
+class Jin10Error(Exception):
+    pass
+
+
+async def uc_request(path: str, params: dict | None = None, token: str | None = None) -> dict:
+    headers = {**HEADERS, **({"x-token": token} if token else {})}
+    try:
+        async with httpx.AsyncClient(timeout=10, trust_env=False) as client:
+            response = await client.get(UC_URL + path, params=params, headers=headers)
+            response.raise_for_status()
+            body = response.json()
+        if not isinstance(body, dict) or body.get("status") != 200:
+            raise Jin10Error("金十未接受请求，请重新扫码或稍后重试")
+        return body
+    except (httpx.HTTPError, ValueError) as exc:
+        # Upstream messages and request URLs may contain credentials.
+        raise Jin10Error("金十连接失败，请稍后重试") from exc
+
+
+async def generate_qr() -> str:
+    body = await uc_request("/qrcode/generate", {"device_type": "web"})
+    value = body.get("data")
+    if isinstance(value, dict):
+        value = value.get("token")
+    if not isinstance(value, str) or not value or len(value) > 2048:
+        raise Jin10Error("金十二维码响应格式已变化")
+    return value
+
+
+def qr_image(token: str) -> str:
+    from urllib.parse import urlencode
+    image = qrcode.make("https://www.jin10.com/?" + urlencode({"action": "login", "tag": token}))
+    stream = BytesIO()
+    image.save(stream, format="PNG")
+    return "data:image/png;base64," + base64.b64encode(stream.getvalue()).decode()
+
+
+async def poll_qr(token: str) -> tuple[str, str | None]:
+    body = await uc_request("/qrcode/try_login", {"token": token})
+    data = body.get("data")
+    if data is None:
+        return "pending", None
+    if not isinstance(data, dict):
+        raise Jin10Error("金十扫码状态响应格式已变化")
+    credential = data.get("token")
+    if isinstance(credential, str) and credential:
+        # Confirm that a QR success really yields an authenticated account.
+        info = await uc_request("/userinfo", token=credential)
+        if not isinstance(info.get("data"), dict) or not info["data"]:
+            raise Jin10Error("金十登录态验证失败")
+        return "connected", credential
+    if str(data.get("qr_status", "")).lower() in ("expired", "invalid", "timeout"):
+        return "expired", None
+    return "pending", None