feat(android+web/diagnostics): on-device debug reporter + admin timeline (M9)

Android: a gated DiagnosticsReporter taps connectivity, server-health,
UPnP drops/player-state/route, power (Doze/battery-opt/screen), and
app fg/bg, plus a heartbeat snapshotting Sonos-vs-local position — the
locked-phone desync signal. Events buffer in a Room ring buffer
(deliberately NOT the MutationQueue: high-volume best-effort telemetry
that must survive the dead zone being debugged) and DiagnosticsUploader
drains them on a tick / health-recovery / sign-in.

Gating: the account flag (users.debug_mode_enabled) reaches the device
via a new /api/me refresh in AuthController; a per-device local OFF
switch lives in Settings. Reporter runs only when enabled && !optOut;
disabling drops the unsent buffer.

Web admin: /admin/diagnostics — pick account+device+kind+time-window,
see a chronological timeline, flip an account's debug mode remotely, and
Copy-JSON / Download-NDJSON the slice for analysis.

Room schema 6→7 (new diagnostic_events table + auth_session.diagnosticsOptOut;
pre-v1 destructive fallback).

Refs Scribe M9 (#119), tasks #1174 #1175 #1176 #1177.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01K55iTxn95BtshocgdE1shW

web/src/lib/api/admin.ts

@@ -391,6 +391,7 @@ export type AdminUser = {
   display_name: string | null;
   is_admin: boolean;
   auto_approve_requests: boolean;
+  debug_mode_enabled: boolean;
   created_at: string;
 };
 
@@ -451,6 +452,12 @@ export async function updateUserAutoApprove(id: string, autoApprove: boolean): P
   return api.put<AdminUser>(`/api/admin/users/${id}/auto-approve`, { auto_approve: autoApprove });
 }
 
+// Flip an account's diagnostics/debug-reporting opt-in (M9). Admin-set;
+// the client obeys it (with a local per-device OFF switch).
+export async function updateUserDebugMode(id: string, enabled: boolean): Promise<AdminUser> {
+  return api.put<AdminUser>(`/api/admin/users/${id}/debug-mode`, { enabled });
+}
+
 export function createAdminUsersQuery() {
   return createQuery({
     queryKey: qk.adminUsers(),
@@ -497,3 +504,82 @@ export function createSMTPConfigQuery() {
     staleTime: 60_000
   });
 }
+
+// Device diagnostics (M9) ---------------------------------------------------
+
+// Coarse event category. The finer event sub-type lives inside `payload`.
+export type DiagnosticKind =
+  | 'connectivity'
+  | 'upnp_sync'
+  | 'power'
+  | 'lifecycle'
+  | 'heartbeat'
+  | 'http';
+
+export type AdminDiagnostic = {
+  id: string;
+  user_id: string;
+  username: string;
+  client_id: string;
+  app_version?: string;
+  os_version?: string;
+  kind: DiagnosticKind | string;
+  payload: Record<string, unknown>;
+  occurred_at: string;
+  received_at: string;
+};
+
+export type AdminDiagnosticDevice = {
+  client_id: string;
+  user_id: string;
+  username: string;
+  app_version: string;
+  os_version: string;
+  last_seen: string;
+  event_count: number;
+};
+
+export type DiagnosticsFilter = {
+  userId?: string;
+  clientId?: string;
+  kind?: string;
+  from?: string; // RFC3339
+  to?: string; // RFC3339
+  limit?: number;
+};
+
+export async function listAdminDiagnostics(f: DiagnosticsFilter): Promise<AdminDiagnostic[]> {
+  const params = new URLSearchParams();
+  if (f.userId) params.set('user_id', f.userId);
+  if (f.clientId) params.set('client_id', f.clientId);
+  if (f.kind) params.set('kind', f.kind);
+  if (f.from) params.set('from', f.from);
+  if (f.to) params.set('to', f.to);
+  if (f.limit !== undefined) params.set('limit', String(f.limit));
+  const qs = params.toString();
+  return api.get<AdminDiagnostic[]>(qs ? `/api/admin/diagnostics?${qs}` : '/api/admin/diagnostics');
+}
+
+export async function listDiagnosticDevices(userId?: string): Promise<AdminDiagnosticDevice[]> {
+  const qs = userId ? `?user_id=${userId}` : '';
+  return api.get<AdminDiagnosticDevice[]>(`/api/admin/diagnostics/devices${qs}`);
+}
+
+export function createAdminDiagnosticsQuery(f: DiagnosticsFilter) {
+  return createQuery({
+    queryKey: qk.adminDiagnostics(f as Record<string, string | number | undefined>),
+    queryFn: () => listAdminDiagnostics(f),
+    // The operator enables debug then watches events stream in; a short
+    // poll keeps the timeline live without manual refresh.
+    refetchInterval: 10_000,
+    staleTime: 5_000
+  });
+}
+
+export function createDiagnosticDevicesQuery(userId?: string) {
+  return createQuery({
+    queryKey: qk.adminDiagnosticDevices(userId),
+    queryFn: () => listDiagnosticDevices(userId),
+    staleTime: 15_000
+  });
+}

web/src/lib/api/queries.ts

@@ -50,6 +50,10 @@ export const qk = {
   coverProviders:         ()              => ['coverProviders'] as const,
   adminUsers:             ()              => ['adminUsers'] as const,
   adminInvites:           ()              => ['adminInvites'] as const,
+  adminDiagnostics:       (f: Record<string, string | number | undefined>) =>
+    ['adminDiagnostics', f] as const,
+  adminDiagnosticDevices: (userId?: string) =>
+    ['adminDiagnosticDevices', { userId: userId ?? 'all' }] as const,
   smtpConfig:             ()              => ['smtpConfig'] as const,
   suggestions:            (limit?: number) =>
     ['suggestions', { limit: limit ?? 12 }] as const,

web/src/lib/components/AdminTabs.svelte

@@ -9,6 +9,7 @@
     { href: '/admin/requests',        label: 'Requests'        },
     { href: '/admin/quarantine',      label: 'Quarantine'      },
     { href: '/admin/playback-errors', label: 'Playback errors' },
+    { href: '/admin/diagnostics',     label: 'Diagnostics'     },
     { href: '/admin/users',           label: 'Users'           }
   ];