feat(admin): metadata-profile picker on integrations page

Persists the operator's metadata-profile choice alongside quality
profile + root folder. Defaults to the first profile Lidarr returns
(usually 'Standard' on a vanilla install) so the common case is
zero-click; operators with custom profiles like 'Singles only' can pick
explicitly.

Backend:
- Migration 0013: adds nullable default_metadata_profile_id to
  lidarr_config. Existing rows get NULL and the service falls back to
  fetch-and-pick-first until they save.
- Updated lidarr_config queries + sqlc + lidarrconfig.Config + admin
  view/put body to round-trip the new field.
- handlePutLidarrConfig requires it (along with QP and root folder)
  when enabled=true — matches the existing missing_defaults gate.
- New GET /api/admin/lidarr/metadata-profiles handler + lidarr.Client
  ListMetadataProfiles (GET /api/v1/metadataprofile, same shape as
  the quality-profile endpoint).
- lidarrrequests.Approve prefers cfg.DefaultMetadataProfileID; falls
  back to the fetch-list path only when 0 (back-compat for upgraders).

Frontend:
- LidarrConfig type + LidarrMetadataProfile type + qk.lidarrMetadataProfiles.
- listMetadataProfiles + createMetadataProfilesQuery client helpers.
- Integrations page: third <select> picker, auto-defaults to first
  profile when the saved value is 0, sends the new field on save and
  clears it on disconnect.
- Updated test fixtures + the duplicate 'Standard' option string in
  the dropdown-populates assertion.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

web/src/routes/admin/integrations/integrations.test.ts

@@ -13,6 +13,7 @@ vi.mock('@tanstack/svelte-query', async (orig) => {
 vi.mock('$lib/api/admin', () => ({
   createLidarrConfigQuery: vi.fn(),
   createQualityProfilesQuery: vi.fn(),
+  createMetadataProfilesQuery: vi.fn(),
   createRootFoldersQuery: vi.fn(),
   putLidarrConfig: vi.fn(),
   testLidarrConnection: vi.fn()
@@ -22,6 +23,7 @@ import IntegrationsPage from './+page.svelte';
 import {
   createLidarrConfigQuery,
   createQualityProfilesQuery,
+  createMetadataProfilesQuery,
   createRootFoldersQuery,
   putLidarrConfig,
   testLidarrConnection
@@ -32,6 +34,7 @@ const cfgConnected: LidarrConfig = {
   base_url: 'http://lidarr.local',
   api_key: '***',
   default_quality_profile_id: 1,
+  default_metadata_profile_id: 1,
   default_root_folder_path: '/music'
 };
 
@@ -40,6 +43,7 @@ const cfgUnset: LidarrConfig = {
   base_url: '',
   api_key: '',
   default_quality_profile_id: 0,
+  default_metadata_profile_id: 0,
   default_root_folder_path: ''
 };
 
@@ -59,6 +63,14 @@ function setup(opts: { config?: LidarrConfig } = {}) {
       ]
     })
   );
+  (createMetadataProfilesQuery as ReturnType<typeof vi.fn>).mockReturnValue(
+    mockQuery({
+      data: [
+        { id: 1, name: 'Standard' },
+        { id: 2, name: 'Singles only' }
+      ]
+    })
+  );
   (createRootFoldersQuery as ReturnType<typeof vi.fn>).mockReturnValue(
     mockQuery({ data: [{ path: '/music', accessible: true, free_space: 0 }] })
   );
@@ -164,10 +176,12 @@ describe('/admin/integrations', () => {
     );
   });
 
-  test('Quality profile and root folder dropdowns populate from API', () => {
+  test('Quality / metadata / root folder dropdowns populate from API', () => {
     setup();
-    expect(screen.getByText('Standard')).toBeInTheDocument();
+    // 'Standard' appears in both quality + metadata fixtures, so use *AllBy*.
+    expect(screen.getAllByText('Standard').length).toBeGreaterThanOrEqual(2);
     expect(screen.getByText('Lossless')).toBeInTheDocument();
+    expect(screen.getByText('Singles only')).toBeInTheDocument();
     expect(screen.getByText('/music')).toBeInTheDocument();
   });