fix: 停止机器人后UI消失 & UDP send error日志刷屏

- botDisconnected事件改为更新状态而非删除，停止机器人后正确显示离线状态
- 节流UDP send error日志，2秒内重复错误只输出一条汇总

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/ts-protocol/client.ts

@@ -56,11 +56,33 @@ export class TS3Client extends EventEmitter {
     const addr = `${this.options.host}:${this.options.port}`;
     this.logger.info({ addr }, "Connecting to TeamSpeak server (full client protocol)");
 
+    // Throttle repeated "udp send error" warnings (fires every 20ms during playback if UDP breaks)
+    let udpErrorCount = 0;
+    let udpErrorTimer: ReturnType<typeof setTimeout> | null = null;
+    const throttledWarn = (msg: string, ...args: unknown[]) => {
+      if (typeof msg === "string" && msg.includes("udp send error")) {
+        udpErrorCount++;
+        if (udpErrorCount === 1) {
+          this.logger.warn(msg);
+          // After 2 seconds, log a summary and reset
+          udpErrorTimer = setTimeout(() => {
+            if (udpErrorCount > 1) {
+              this.logger.warn(`udp send error (repeated ${udpErrorCount} times, connection may be lost)`);
+            }
+            udpErrorCount = 0;
+            udpErrorTimer = null;
+          }, 2000);
+        }
+        return;
+      }
+      this.logger.warn(msg);
+    };
+
     this.client = new TS3FullClient(this.identity, addr, this.options.nickname, {
       logger: {
         debug: (msg) => this.logger.debug(msg),
         info: (msg) => this.logger.info(msg),
-        warn: (msg) => this.logger.warn(msg),
+        warn: throttledWarn,
         error: (msg) => this.logger.error(msg),
       },
     });

src/web/websocket.ts

@@ -65,7 +65,11 @@ export function setupWebSocket(
     };
 
     const onDisconnected = () => {
-      broadcast({ type: "botDisconnected", botId: bot.id });
+      broadcast({
+        type: "botDisconnected",
+        botId: bot.id,
+        status: bot.getStatus(),
+      });
     };
 
     bot.on("stateChange", onStateChange);

web/src/composables/useWebSocket.ts

@@ -40,7 +40,21 @@ export function useWebSocket() {
           store.updateBotStatus(data.botId, data.status);
           break;
         case 'botDisconnected':
-          store.removeBotStatus(data.botId);
+          // Bot disconnected from TS3 but still exists — update status, don't remove
+          if (data.status) {
+            store.updateBotStatus(data.botId, data.status);
+          } else {
+            const existing = store.bots.find((b) => b.id === data.botId);
+            if (existing) {
+              store.updateBotStatus(data.botId, {
+                ...existing,
+                connected: false,
+                playing: false,
+                paused: false,
+                currentSong: null,
+              });
+            }
+          }
           break;
       }
     };