feat(fm): let each web user link their own NetEase account for personal FM (#164)

With several people sharing one bot, personal FM always followed the one
account the bot was logged in with. Each signed-in (non-guest) web user
can now scan a QR code under Settings → 账户 to link their own NetEase
account; FM they start from the WebUI then comes from their account.

- user_music_cookies table (per user + platform, dropped with the user).
- NeteaseProvider.pollQrLogin returns the cookie without storing it, so
  a personal login can never replace the bot's shared account;
  checkQrCodeStatus is now built on it. withCookie gives a view bound to
  another account.
- /api/me/music/netease: status / qrcode / qrcode/status / unlink, acting
  only on req.user. The cookie never leaves the server.
- POST /api/player/:botId/fm uses the caller's linked account for
  NetEase. Songs still resolve through the shared provider when played.

TeamSpeak chat !fm keeps using the shared account: chat users are not
tied to web accounts.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

src/web/api/personal-music.test.ts

@@ -0,0 +1,125 @@
+import { describe, it, expect, vi } from "vitest";
+import express from "express";
+import request from "supertest";
+import pino from "pino";
+import { createDatabase } from "../../data/database.js";
+import { createPersonalMusicRouter } from "./personal-music.js";
+import { createPlayerRouter } from "./player.js";
+
+function mount() {
+  const db = createDatabase(":memory:");
+  db.db
+    .prepare("INSERT INTO users (id, username, passwordHash, createdAt, updatedAt, role) VALUES (?,?,?,?,?,?)")
+    .run("u1", "alice", "x", 0, 0, "member");
+  const personalView = {
+    getAuthStatus: vi.fn(async () => ({ loggedIn: true, nickname: "Alice163" })),
+  };
+  const provider: any = {
+    platform: "netease",
+    getQrCode: vi.fn(async () => ({ qrUrl: "u", qrImg: "data:img", key: "k1" })),
+    pollQrLogin: vi.fn(async () => ({ status: "waiting" })),
+    withCookie: vi.fn(() => personalView),
+    setCookie: vi.fn(),
+  };
+  const app = express();
+  app.use(express.json());
+  app.use((req, _res, next) => {
+    (req as any).user = { id: "u1", username: "alice", role: "member" };
+    next();
+  });
+  app.use("/api/me/music", createPersonalMusicRouter(db, provider, pino({ level: "silent" })));
+  return { app, db, provider, personalView };
+}
+
+describe("personal music account router (#164)", () => {
+  it("reports not linked until the user logs in", async () => {
+    const { app } = mount();
+    const res = await request(app).get("/api/me/music/netease/status");
+    expect(res.status).toBe(200);
+    expect(res.body).toEqual({ linked: false, loggedIn: false });
+  });
+
+  it("creates a QR code", async () => {
+    const { app } = mount();
+    const res = await request(app).post("/api/me/music/netease/qrcode");
+    expect(res.body).toEqual({ qrUrl: "u", qrImg: "data:img", key: "k1" });
+  });
+
+  it("stores the cookie for this user on confirm, never on the shared provider, and never returns it", async () => {
+    const { app, db, provider } = mount();
+    provider.pollQrLogin.mockResolvedValue({ status: "confirmed", cookie: "MUSIC_U=alice" });
+    const res = await request(app).get("/api/me/music/netease/qrcode/status").query({ key: "k1" });
+    expect(res.body).toEqual({ status: "confirmed" });
+    expect(JSON.stringify(res.body)).not.toContain("MUSIC_U");
+    expect(db.getUserMusicCookie("u1", "netease")).toBe("MUSIC_U=alice");
+    expect(provider.setCookie).not.toHaveBeenCalled();
+  });
+
+  it("requires a key to poll", async () => {
+    const { app } = mount();
+    expect((await request(app).get("/api/me/music/netease/qrcode/status")).status).toBe(400);
+  });
+
+  it("reports the linked account's nickname via a view on the user's cookie", async () => {
+    const { app, db, provider } = mount();
+    db.setUserMusicCookie("u1", "netease", "MUSIC_U=alice");
+    const res = await request(app).get("/api/me/music/netease/status");
+    expect(res.body).toEqual({ linked: true, loggedIn: true, nickname: "Alice163" });
+    expect(provider.withCookie).toHaveBeenCalledWith("MUSIC_U=alice");
+  });
+
+  it("unlinks", async () => {
+    const { app, db } = mount();
+    db.setUserMusicCookie("u1", "netease", "MUSIC_U=alice");
+    expect((await request(app).delete("/api/me/music/netease")).status).toBe(200);
+    expect(db.getUserMusicCookie("u1", "netease")).toBeNull();
+  });
+});
+
+describe("web FM uses the caller's linked NetEase account (#164)", () => {
+  async function startFm(opts: { linked: boolean; role?: string; platform?: string }) {
+    const db = createDatabase(":memory:");
+    db.db
+      .prepare("INSERT INTO users (id, username, passwordHash, createdAt, updatedAt, role) VALUES (?,?,?,?,?,?)")
+      .run("u1", "alice", "x", 0, 0, "member");
+    if (opts.linked) db.setUserMusicCookie("u1", "netease", "MUSIC_U=alice");
+    const personal = { platform: "netease", personal: true };
+    const shared: any = { platform: "netease", pollQrLogin: vi.fn(), withCookie: vi.fn(() => personal) };
+    const qq: any = { platform: "qq" };
+    const bot = {
+      id: "b1",
+      getProviderFor: (p: string) => (p === "qq" ? qq : shared),
+      startFm: vi.fn(async (_provider: unknown) => "Personal FM started"),
+    };
+    const botManager: any = { getBot: () => bot };
+    const app = express();
+    app.use(express.json());
+    app.use((req, _res, next) => {
+      (req as any).user = {
+        id: "u1", username: "alice", role: opts.role ?? "member",
+        capabilities: new Set(["player.control"]), bots: "all", guest: { playMode: true },
+      };
+      next();
+    });
+    app.use("/api/player", createPlayerRouter(botManager, pino({ level: "silent" }), db));
+    const res = await request(app).post("/api/player/b1/fm").send({ platform: opts.platform ?? "netease" });
+    return { res, bot, shared, personal, qq };
+  }
+
+  it("starts FM on the user's own account when linked", async () => {
+    const { res, bot, shared, personal } = await startFm({ linked: true });
+    expect(res.status).toBe(200);
+    expect(shared.withCookie).toHaveBeenCalledWith("MUSIC_U=alice");
+    expect(bot.startFm.mock.calls[0][0]).toBe(personal);
+  });
+
+  it("falls back to the shared account when the user has not linked one", async () => {
+    const { bot, shared } = await startFm({ linked: false });
+    expect(bot.startFm.mock.calls[0][0]).toBe(shared);
+  });
+
+  it("leaves other platforms alone", async () => {
+    const { bot, qq } = await startFm({ linked: true, platform: "qq" });
+    expect(bot.startFm.mock.calls[0][0]).toBe(qq);
+  });
+});