feat(vision): prioritize main model for image recognition with multi-provider fallback

- Add call_vision method to all bot implementations (DashScope, Claude,
  Gemini, ZhipuAI, MiniMax, Doubao, Moonshot, OpenAICompatibleBot)
  using each vendor's native multimodal API format
- Remove call_with_tools/call_vision from Bot base class to fix MRO
  shadowing issue with OpenAICompatibleBot mixin
- Refactor vision tool provider resolution: MainModel → other configured
  models (auto-discovered) → OpenAI → LinkAI, with automatic fallback
- Return actual model name used in call_vision responses
- Sync config.json API keys to .env bidirectionally on startup
- Fix bot instance cache to detect bot_type/use_linkai config changes
- Add SSE reconnection support for web console
- Preserve image path hints in Gemini text for correct vision tool calls
- Update docs/tools/vision.mdx

channel/web/web_channel.py

@@ -329,14 +329,18 @@ class WebChannel(ChatChannel):
         """
         SSE generator for a given request_id.
         Yields UTF-8 encoded bytes to avoid WSGI Latin-1 mangling.
+        Supports client reconnection: the queue is only removed after a
+        "done" event is consumed, so a new GET /stream with the same
+        request_id can resume reading remaining events.
         """
         if request_id not in self.sse_queues:
             yield b"data: {\"type\": \"error\", \"message\": \"invalid request_id\"}\n\n"
             return
 
         q = self.sse_queues[request_id]
-        timeout = 300  # 5 minutes max
-        deadline = time.time() + timeout
+        idle_timeout = 600  # 10 minutes without any real event
+        deadline = time.time() + idle_timeout
+        done = False
 
         try:
             while time.time() < deadline:
@@ -346,13 +350,18 @@ class WebChannel(ChatChannel):
                     yield b": keepalive\n\n"
                     continue
 
+                # Real event received, reset idle deadline
+                deadline = time.time() + idle_timeout
+
                 payload = json.dumps(item, ensure_ascii=False)
                 yield f"data: {payload}\n\n".encode("utf-8")
 
                 if item.get("type") == "done":
+                    done = True
                     break
         finally:
-            self.sse_queues.pop(request_id, None)
+            if done:
+                self.sse_queues.pop(request_id, None)
 
     def poll_response(self):
         """