feat: add web search block functionality and integrate with existing plugins

- Introduced a new web search block plugin to handle web search queries and results.
- Updated copilot, doc block, and pro block plugins to include web search context in AI completions.
- Implemented utility functions for parsing and building web search markdown.
- Enhanced API to support web search requests and responses.
- Added configuration for web search URL and timeout settings.
- Updated size limit checks to account for web search content.

backend/main.py

@@ -5,6 +5,7 @@ import logging
 import os
 import uuid
 from contextlib import suppress
+from datetime import datetime
 from typing import Optional
 
 from fastapi import FastAPI, File, Form, HTTPException, Request, Response, Security, UploadFile
@@ -27,6 +28,7 @@ from job_handlers import (
     ocr_handler,
     pro_completion_handler,
     tts_handler,
+    web_search_handler,
 )
 from job_system import (
     InMemoryJobManager,
@@ -87,6 +89,14 @@ class ProCompletionRequest(BaseModel):
     user_preferences: Optional[UserPreferences] = None
 
 
+class WebSearchRequest(BaseModel):
+    prefix: str
+    suffix: str
+    languageId: str = "markdown"
+    privacy_mode: bool = False
+    user_preferences: Optional[UserPreferences] = None
+
+
 class CancelCompletionRequest(BaseModel):
     request_id: str
     reason: str = "abort"
@@ -267,18 +277,24 @@ async def _authorize_request(
 
 
 def _register_handlers() -> None:
+    """注册所有任务处理器。每次调用都会重新获取当前 manager 实例并强制注册，
+    确保 Redis 重连或实例重建后处理器不会丢失。"""
     global _handlers_registered
-    if _handlers_registered:
-        return
     manager = get_job_manager()
+    # 强制清空旧 handlers，避免重复注册累积
+    manager.handlers.clear()
     manager.register_handler("completion", completion_handler)
     manager.register_handler("pro_completion", pro_completion_handler)
+    manager.register_handler("web_search", web_search_handler)
     manager.register_handler("compress", compress_handler)
     manager.register_handler("ocr", ocr_handler)
     manager.register_handler("convert", convert_handler)
     manager.register_handler("tts", tts_handler)
     manager.register_handler("asr", asr_handler)
     _handlers_registered = True
+    
+    # 打印注册信息便于调试
+    logger.info("handlers registered: %s", list(manager.handlers.keys()))tered: %s", list(manager.handlers.keys()))
 
 
 def _sse(event: str, data: dict) -> str:
@@ -375,7 +391,7 @@ async def _guard_api_request(request: Request, *, scope: str) -> tuple[RiskIdent
     return identity, decision
 
 
-def _estimate_completion_chars(req: CompletionRequest | ProCompletionRequest) -> int:
+def _estimate_completion_chars(req: CompletionRequest | ProCompletionRequest | WebSearchRequest) -> int:
     return len(req.prefix or "") + len(req.suffix or "") + len(getattr(req, "instruction", "") or "")
 
 
@@ -551,6 +567,45 @@ async def cancel_pro_completion(req: CancelCompletionRequest, auth: dict = Secur
     return await _cancel_job(req.request_id or "", req.reason)
 
 
+@app.post("/v1/web-search")
+async def create_web_search(
+    request: Request,
+    req: WebSearchRequest,
+    auth: dict = Security(_authorize_request),
+):
+    del auth
+    body = {
+        "prefix": req.prefix,
+        "suffix": req.suffix,
+        "languageId": req.languageId,
+        "privacy_mode": req.privacy_mode,
+        "user_preferences": _serialize_preferences(req.user_preferences),
+    }
+    try:
+        identity, payload = await _prepare_llm_payload(
+            request,
+            job_type="web_search",
+            request_body=body,
+            raw_size=_estimate_completion_chars(req),
+            token_source_text=f"{req.prefix}\n{req.suffix}",
+        )
+        payload["created_at"] = datetime.utcnow().isoformat()
+        job_id = await _queue_job("web_search", payload, identity.request_id)
+    except RiskRejected as exc:
+        return _risk_json_response(_request_identity(request), exc.decision)
+    except QueueFullError as exc:
+        return JSONResponse({"error": str(exc), "request_id": _request_id(request)}, status_code=429)
+    except JobSystemError as exc:
+        return JSONResponse({"error": str(exc), "request_id": _request_id(request)}, status_code=503)
+    return await _stream_job(job_id)
+
+
+@app.post("/v1/web-search/cancel")
+async def cancel_web_search(req: CancelCompletionRequest, auth: dict = Security(_authorize_request)):
+    del auth
+    return await _cancel_job(req.request_id or "", req.reason)
+
+
 @app.get("/v1/pro/completions/status/{request_id}")
 async def get_pro_completion_status(request_id: str, auth: dict = Security(_authorize_request)):
     del auth