feat(p3): add discovery, telegram notifications, and one-click favorites

Implement WBI video search with legacy fallback, classification scoring, candidate pool, permanent seen-aid dedupe, blacklist filtering, and batched Telegram notifications. Add write client for fav deal/sort, target-folder selection, insertion position calculation, read-back verification, fav_action locking, retry on failure, ignore and blacklist actions. Wire discovery, candidate cleanup, Telegram long polling, and new discover/candidates CLI commands into the scheduler. Add migration v3 for candidate duration and index stats.

reaction_board/bilibili/write_client.py

@@ -0,0 +1,60 @@
+# -*- coding: utf-8 -*-
+"""B 站收藏夹写客户端（``deal`` / ``sort``）。
+
+只应使用 ``bilibili.write`` 凭据构造。
+"""
+
+from __future__ import annotations
+
+import urllib.parse
+from typing import Any, Mapping
+
+from .client import (
+    BASE,
+    BilibiliClient,
+    BilibiliHTTPError,
+    BilibiliProtocolError,
+)
+
+
+class BilibiliWriteClient(BilibiliClient):
+    def post_form(self, url: str, data: Mapping[str, Any]) -> dict[str, Any]:
+        self.pacer.wait()
+        headers = self._headers(auth=True)
+        headers["content-type"] = "application/x-www-form-urlencoded"
+        body = urllib.parse.urlencode(data).encode("utf-8")
+        response = self.transport.request(
+            "POST", url, headers, data=body, timeout=self.timeout
+        )
+        if response.status >= 400:
+            raise BilibiliHTTPError(
+                response.status, response.body.decode("utf-8", "replace")[:200]
+            )
+        payload = response.json()
+        if not isinstance(payload, dict):
+            raise BilibiliProtocolError("写接口响应顶层不是 JSON 对象")
+        if payload.get("code") != 0:
+            raise self._api_error(payload)
+        return payload
+
+    def deal(self, aid: int, folder_id: int) -> dict[str, Any]:
+        return self.post_form(
+            f"{BASE}/x/v3/fav/resource/deal",
+            {
+                "rid": int(aid),
+                "type": 2,
+                "add_media_ids": int(folder_id),
+                "del_media_ids": "",
+                "csrf": self.csrf,
+            },
+        )
+
+    def sort(self, media_id: int, sort_spec: str) -> dict[str, Any]:
+        return self.post_form(
+            f"{BASE}/x/v3/fav/resource/sort",
+            {
+                "media_id": int(media_id),
+                "sort": sort_spec,
+                "csrf": self.csrf,
+            },
+        )