feat: implement server password login, YouTube source, and improved bot selector UI

- **TS server password** (#7/#9): add serverPassword field across database,
  manager, bot API, and Settings UI — allows joining password-protected servers
- **YouTube audio source** (#1/#10): new YouTubeProvider using yt-dlp binary;
  adds -y flag in chat commands, /api/music supports platform=youtube,
  YouTube badge in SongCard, yt-dlp-wrap npm dependency
- **Bot selector UI** (#14): selector always visible (not just when >1 bot),
  bigger button with border and play-state indicator; per-bot URL routing at
  /bot/:id with BotRedirect view; copy-link button in dropdown

Closes #1, #7, #9, #10, #14

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/bot/instance.ts

@@ -23,6 +23,7 @@ export interface BotInstanceOptions {
   neteaseProvider: MusicProvider;
   qqProvider: MusicProvider;
   bilibiliProvider: MusicProvider;
+  youtubeProvider: MusicProvider;
   database: BotDatabase;
   config: BotConfig;
   logger: Logger;
@@ -51,6 +52,7 @@ export class BotInstance extends EventEmitter {
   private neteaseProvider: MusicProvider;
   private qqProvider: MusicProvider;
   private bilibiliProvider: MusicProvider;
+  private youtubeProvider: MusicProvider;
   private database: BotDatabase;
   private config: BotConfig;
   private logger: Logger;
@@ -65,6 +67,7 @@ export class BotInstance extends EventEmitter {
     this.neteaseProvider = options.neteaseProvider;
     this.qqProvider = options.qqProvider;
     this.bilibiliProvider = options.bilibiliProvider;
+    this.youtubeProvider = options.youtubeProvider;
     this.database = options.database;
     this.config = options.config;
     this.logger = options.logger.child({ botId: this.id });
@@ -217,14 +220,16 @@ export class BotInstance extends EventEmitter {
     }
   }
 
-  getProviderFor(platform: "netease" | "qq" | "bilibili"): MusicProvider {
+  getProviderFor(platform: "netease" | "qq" | "bilibili" | "youtube"): MusicProvider {
     if (platform === "bilibili") return this.bilibiliProvider;
+    if (platform === "youtube") return this.youtubeProvider;
     return platform === "qq" ? this.qqProvider : this.neteaseProvider;
   }
 
   private getProvider(flags: Set<string>): MusicProvider {
     if (flags.has("b")) return this.bilibiliProvider;
     if (flags.has("q")) return this.qqProvider;
+    if (flags.has("y")) return this.youtubeProvider;
     return this.neteaseProvider;
   }
 
@@ -477,6 +482,7 @@ export class BotInstance extends EventEmitter {
       `${p}play <song>  — Search and play`,
       `${p}play -q <song> — Search from QQ Music`,
       `${p}play -b <song> — Search from BiliBili`,
+      `${p}play -y <song> — Search from YouTube (yt-dlp)`,
       `${p}add <song>   — Add to queue`,
       `${p}pause/resume — Pause/resume`,
       `${p}next/prev    — Next/previous`,

src/bot/manager.ts

@@ -4,6 +4,7 @@ import {
   type BotInstanceOptions,
 } from "./instance.js";
 import type { MusicProvider } from "../music/provider.js";
+import { YouTubeProvider } from "../music/youtube.js";
 import type { BotDatabase } from "../data/database.js";
 import type { BotConfig } from "../data/config.js";
 import type { Logger } from "../logger.js";
@@ -23,6 +24,8 @@ export interface CreateBotParams {
   serverProtocol?: ServerProtocol;
   /** API key for TS6 HTTP Query (port 10080/10443). */
   ts6ApiKey?: string;
+  /** Password required to join the TS server. */
+  serverPassword?: string;
 }
 
 export class BotManager {
@@ -30,6 +33,7 @@ export class BotManager {
   private neteaseProvider: MusicProvider;
   private qqProvider: MusicProvider;
   private bilibiliProvider: MusicProvider;
+  private youtubeProvider: MusicProvider;
   private database: BotDatabase;
   private config: BotConfig;
   private logger: Logger;
@@ -45,6 +49,7 @@ export class BotManager {
     this.neteaseProvider = neteaseProvider;
     this.qqProvider = qqProvider;
     this.bilibiliProvider = bilibiliProvider;
+    this.youtubeProvider = new YouTubeProvider();
     this.database = database;
     this.config = config;
     this.logger = logger;
@@ -63,12 +68,14 @@ export class BotManager {
         nickname: params.nickname,
         defaultChannel: params.defaultChannel,
         channelPassword: params.channelPassword,
+        serverPassword: params.serverPassword,
         serverProtocol: params.serverProtocol,
         ts6ApiKey: params.ts6ApiKey,
       },
       neteaseProvider: this.neteaseProvider,
       qqProvider: this.qqProvider,
       bilibiliProvider: this.bilibiliProvider,
+      youtubeProvider: this.youtubeProvider,
       database: this.database,
       config: this.config,
       logger: this.logger,
@@ -87,6 +94,7 @@ export class BotManager {
       autoStart: params.autoStart ?? false,
       serverProtocol: params.serverProtocol ?? "",
       ts6ApiKey: params.ts6ApiKey ?? "",
+      serverPassword: params.serverPassword ?? "",
     });
 
     this.logger.info({ botId: id, name: params.name }, "Bot instance created");
@@ -118,6 +126,7 @@ export class BotManager {
       channelPassword: params.channelPassword ?? existing.channelPassword,
       serverProtocol: params.serverProtocol ?? existing.serverProtocol,
       ts6ApiKey: params.ts6ApiKey ?? existing.ts6ApiKey,
+      serverPassword: params.serverPassword ?? existing.serverPassword,
     });
     // Update in-memory name immediately (other fields need reconnect)
     const bot = this.bots.get(id);
@@ -157,12 +166,14 @@ export class BotManager {
           nickname: saved.nickname,
           defaultChannel: saved.defaultChannel || undefined,
           channelPassword: saved.channelPassword || undefined,
+          serverPassword: saved.serverPassword || undefined,
           serverProtocol: proto === "ts3" || proto === "ts6" ? proto : undefined,
           ts6ApiKey: saved.ts6ApiKey || undefined,
         },
         neteaseProvider: this.neteaseProvider,
         qqProvider: this.qqProvider,
         bilibiliProvider: this.bilibiliProvider,
+      youtubeProvider: this.youtubeProvider,
         database: this.database,
         config: this.config,
         logger: this.logger,
@@ -204,12 +215,14 @@ export class BotManager {
           identity: saved.identity || undefined,
           defaultChannel: saved.defaultChannel || undefined,
           channelPassword: saved.channelPassword || undefined,
+          serverPassword: saved.serverPassword || undefined,
           serverProtocol: proto === "ts3" || proto === "ts6" ? proto : undefined,
           ts6ApiKey: saved.ts6ApiKey || undefined,
         },
         neteaseProvider: this.neteaseProvider,
         qqProvider: this.qqProvider,
         bilibiliProvider: this.bilibiliProvider,
+      youtubeProvider: this.youtubeProvider,
         database: this.database,
         config: this.config,
         logger: this.logger,