fix: check port availability before starting QQ Music API, update default port to 3200

Prevents EADDRINUSE crash that killed the entire app when port 3200
was still occupied from a previous run.

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

src/data/config.ts

@@ -23,7 +23,7 @@ export function getDefaultConfig(): BotConfig {
     commandPrefix: "!",
     commandAliases: { p: "play", s: "skip", n: "next" },
     neteaseApiPort: 3001,
-    qqMusicApiPort: 3002,
+    qqMusicApiPort: 3200,
     adminPassword: "",
     adminGroups: [],
     autoReturnDelay: 300,