refactor(api): pull feature-resident subsonic clients into lib/api

Move the 5 subsonic api modules that M3 had co-located into features
(subsonicAlbumInfo/Artists/Playlists/Radio/Statistics) into src/lib/api/, the
feature-free infra layer, and drop their feature-barrel re-exports. Consumers
now import these protocol calls directly from @/lib/api/subsonic*; the feature
barrels export only domain UI/hooks/state.

This is the consistent api placement (plan §10.3, revised: ALL subsonic protocol
clients are feature-free infra, not per-feature) and it kills the documented
api-induced feature<->feature cycles: offline->artist/playlist (getArtist/
getPlaylist*), album->artist (getArtistInfo), deviceSync/nowPlaying/orbit->*.
Remaining artist<->album refs are UI-only (OpenArtistRefInline/coerceOpenArtist
Refs) and offline->playlist is store-level (usePlaylistStore) — both deeper,
tracked for M5, not api placement.

Pure move: import specifiers + vi.mock/spy targets repointed; no behaviour
change. tsc 0, lint 0/0, full suite 319 files / 2353 tests green.

Tooling note: barrel-imported and dynamic-import api symbols were split out of
@/features/* to @/lib/api/* (tsc-driven); 12 vi.mock barrels retargeted to the
deep lib module (mock-collapse sweep), AlbumHeader's UI mock left untouched.

src/features/playlist/api/subsonicPlaylists.ts

@@ -1,110 +0,0 @@
-import { invoke } from '@tauri-apps/api/core';
-import { useAuthStore } from '@/store/authStore';
-import { shouldAttemptSubsonicForServer } from '@/utils/network/subsonicNetworkGuard';
-import { api, apiForServer } from '@/lib/api/subsonicClient';
-import type { SubsonicPlaylist, SubsonicSong } from '@/lib/api/subsonicTypes';
-
-export async function getPlaylists(includeOrbit = false): Promise<SubsonicPlaylist[]> {
-  const data = await api<{ playlists: { playlist: SubsonicPlaylist[] } }>('getPlaylists.view', { _t: Date.now() });
-  const all = data.playlists?.playlist ?? [];
-  // Orbit session + outbox playlists are technical internals. They're `public`
-  // so guests can reach them, which means they leak into every UI picker and
-  // even into the Navidrome web client. Filter them out of every UI call;
-  // orbit's own sweep passes `includeOrbit=true`.
-  return includeOrbit ? all : all.filter(p => !p.name.startsWith('__psyorbit_'));
-}
-
-export async function getPlaylist(id: string): Promise<{ playlist: SubsonicPlaylist; songs: SubsonicSong[] }> {
-  const data = await api<{ playlist: SubsonicPlaylist & { entry: SubsonicSong[] } }>('getPlaylist.view', { id });
-  const { entry, ...playlist } = data.playlist;
-  return { playlist, songs: entry ?? [] };
-}
-
-export async function getPlaylistForServer(
-  serverId: string,
-  id: string,
-): Promise<{ playlist: SubsonicPlaylist; songs: SubsonicSong[] }> {
-  if (!shouldAttemptSubsonicForServer(serverId)) {
-    throw new Error('Subsonic unavailable');
-  }
-  const data = await apiForServer<{ playlist: SubsonicPlaylist & { entry: SubsonicSong[] } }>(
-    serverId,
-    'getPlaylist.view',
-    { id },
-  );
-  const { entry, ...playlist } = data.playlist;
-  return { playlist, songs: entry ?? [] };
-}
-
-export async function createPlaylist(name: string, songIds?: string[]): Promise<SubsonicPlaylist> {
-  const params: Record<string, unknown> = { name };
-  if (songIds && songIds.length > 0) {
-    params.songId = songIds;
-  }
-  const data = await api<{ playlist: SubsonicPlaylist }>('createPlaylist.view', params);
-  return data.playlist;
-}
-
-export async function updatePlaylist(id: string, songIds: string[], prevCount = 0): Promise<void> {
-  if (songIds.length > 0) {
-    // createPlaylist with playlistId replaces the existing playlist's songs (Subsonic API 1.14+)
-    await api('createPlaylist.view', { playlistId: id, songId: songIds });
-  } else if (prevCount > 0) {
-    // Axios serialises empty arrays as no params — createPlaylist.view would leave songs unchanged.
-    // Use updatePlaylist.view with explicit index removal to clear the list instead.
-    await api('updatePlaylist.view', {
-      playlistId: id,
-      songIndexToRemove: Array.from({ length: prevCount }, (_, i) => i),
-    });
-  }
-  void import('@/features/offline')
-    .then(m => m.schedulePinnedPlaylistSync(id))
-    .catch(() => {});
-}
-
-export async function updatePlaylistMeta(
-  id: string,
-  name: string,
-  comment: string,
-  isPublic: boolean,
-): Promise<void> {
-  await api('updatePlaylist.view', { playlistId: id, name, comment, public: isPublic });
-}
-
-export async function uploadPlaylistCoverArt(id: string, file: File): Promise<void> {
-  // Navidrome-specific endpoint — handled in Rust to bypass browser CORS restrictions.
-  const { getBaseUrl, getActiveServer } = useAuthStore.getState();
-  const server = getActiveServer();
-  const baseUrl = getBaseUrl();
-  const buffer = await file.arrayBuffer();
-  const fileBytes = Array.from(new Uint8Array(buffer));
-  await invoke('upload_playlist_cover', {
-    serverUrl: baseUrl,
-    playlistId: id,
-    username: server?.username ?? '',
-    password: server?.password ?? '',
-    fileBytes,
-    mimeType: file.type || 'image/jpeg',
-  });
-}
-
-export async function uploadArtistImage(id: string, file: File): Promise<void> {
-  // Navidrome-specific endpoint — handled in Rust to bypass browser CORS restrictions.
-  const { getBaseUrl, getActiveServer } = useAuthStore.getState();
-  const server = getActiveServer();
-  const baseUrl = getBaseUrl();
-  const buffer = await file.arrayBuffer();
-  const fileBytes = Array.from(new Uint8Array(buffer));
-  await invoke('upload_artist_image', {
-    serverUrl: baseUrl,
-    artistId: id,
-    username: server?.username ?? '',
-    password: server?.password ?? '',
-    fileBytes,
-    mimeType: file.type || 'image/jpeg',
-  });
-}
-
-export async function deletePlaylist(id: string): Promise<void> {
-  await api('deletePlaylist.view', { id });
-}

src/features/playlist/hooks/usePlaylistsLibraryScopeCounts.ts

@@ -1,6 +1,6 @@
 import { useEffect, useState } from 'react';
 import { filterSongsToActiveLibrary } from '@/lib/api/subsonicLibrary';
-import { getPlaylist } from '@/features/playlist/api/subsonicPlaylists';
+import { getPlaylist } from '@/lib/api/subsonicPlaylists';
 import type { SubsonicPlaylist } from '@/lib/api/subsonicTypes';
 import { useOfflineBrowseContext } from '@/features/offline';
 

src/features/playlist/index.ts

@@ -10,7 +10,6 @@
  * `playlistDetailHelpers` (shared with offline + favorites; keeping it here
  * would create a playlist⟷offline barrel cycle → lib/shared in M4).
  */
-export * from './api/subsonicPlaylists';
 export * from './hooks/usePlaylistBulkPlayCallbacks';
 export * from './hooks/usePlaylistCovers';
 export * from './hooks/usePlaylistDerived';

src/features/playlist/pages/PlaylistDetail.tsx

@@ -1,4 +1,4 @@
-import { updatePlaylist } from '@/features/playlist/api/subsonicPlaylists';
+import { updatePlaylist } from '@/lib/api/subsonicPlaylists';
 import type { SubsonicPlaylist, SubsonicSong } from '@/lib/api/subsonicTypes';
 import React, { useEffect, useState, useCallback, useMemo } from 'react';
 import { useParams, useNavigate, useLocation } from 'react-router-dom';

src/features/playlist/store/playlistStore.ts

@@ -1,8 +1,8 @@
-import { getPlaylists } from '@/features/playlist/api/subsonicPlaylists';
+import { getPlaylists } from '@/lib/api/subsonicPlaylists';
 import type { SubsonicPlaylist } from '@/lib/api/subsonicTypes';
 import { create } from 'zustand';
 import { persist } from 'zustand/middleware';
-import { createPlaylist as apiCreatePlaylist } from '@/features/playlist/api/subsonicPlaylists';
+import { createPlaylist as apiCreatePlaylist } from '@/lib/api/subsonicPlaylists';
 import { useAuthStore } from '@/store/authStore';
 import { isOfflineBrowseActive } from '@/features/offline';
 import { fetchOfflineBrowsablePlaylists } from '@/features/offline';

src/features/playlist/utils/playPlaylistById.ts

@@ -1,4 +1,4 @@
-import { getPlaylist } from '@/features/playlist/api/subsonicPlaylists';
+import { getPlaylist } from '@/lib/api/subsonicPlaylists';
 import { songToTrack } from '@/utils/playback/songToTrack';
 import { usePlayerStore } from '@/store/playerStore';
 import { playPlaylistAll } from '@/features/playlist/utils/playlistBulkPlayActions';

src/features/playlist/utils/runPlaylistLoad.ts

@@ -1,5 +1,5 @@
 import type React from 'react';
-import { getPlaylist } from '@/features/playlist/api/subsonicPlaylists';
+import { getPlaylist } from '@/lib/api/subsonicPlaylists';
 import { filterSongsToActiveLibrary } from '@/lib/api/subsonicLibrary';
 import type { SubsonicPlaylist, SubsonicSong } from '@/lib/api/subsonicTypes';
 import { useAuthStore } from '@/store/authStore';

src/features/playlist/utils/runPlaylistSaveMeta.ts

@@ -1,5 +1,5 @@
 import type { TFunction } from 'i18next';
-import { getPlaylist, updatePlaylistMeta, uploadPlaylistCoverArt } from '@/features/playlist/api/subsonicPlaylists';
+import { getPlaylist, updatePlaylistMeta, uploadPlaylistCoverArt } from '@/lib/api/subsonicPlaylists';
 import type { SubsonicPlaylist } from '@/lib/api/subsonicTypes';
 import { showToast } from '@/utils/ui/toast';
 

src/features/playlist/utils/runPlaylistsActions.ts

@@ -1,6 +1,6 @@
 import type React from 'react';
 import type { TFunction } from 'i18next';
-import { deletePlaylist, getPlaylist, updatePlaylist } from '@/features/playlist/api/subsonicPlaylists';
+import { deletePlaylist, getPlaylist, updatePlaylist } from '@/lib/api/subsonicPlaylists';
 import type { SubsonicPlaylist } from '@/lib/api/subsonicTypes';
 import { usePlaylistStore } from '@/features/playlist/store/playlistStore';
 import { showToast } from '@/utils/ui/toast';