Merge origin/main into dev: sync bug fixes from main

Merges 4 PRs from main:
- PR#15: Fix ffmpeg spawn failure causing infinite retry loop
- PR#16: Fix Docker restart crash (respect autoStart flag, persist identity)
- PR#17: Add missing "play" script to package.json
- PR#18: Add detailed update/upgrade instructions to README

Conflict resolution in src/data/database.ts:
- Combined dev's serverProtocol/ts6ApiKey fields with main's identity field
- Extended migrateSchema() to also migrate serverProtocol and ts6ApiKey columns
- Updated SQL schema and upsert query to include all three new columns

src/bot/instance.ts

@@ -268,6 +268,8 @@ export class BotInstance extends EventEmitter {
     this.queue.add({ ...song, platform: provider.platform });
     this.queue.play();
 
+    // Reset failure counter on user-initiated play
+    this.player.resetFailures();
     const ok = await this.resolveAndPlay(this.queue.current()!);
     if (!ok) return `Cannot play: ${song.name}`;
     return `Now playing: ${song.name} - ${song.artist}`;
@@ -561,4 +563,8 @@ export class BotInstance extends EventEmitter {
   isConnected(): boolean {
     return this.connected;
   }
+
+  getIdentityExport(): string | undefined {
+    return this.tsClient.getIdentityExport();
+  }
 }