feat(ui): add Now Playing panel for admins (#4209)

* feat(ui): add Now Playing panel and integrate now playing count updates

Signed-off-by: Deluan <deluan@navidrome.org>

* fix: check return value in test to satisfy linter

* fix: format React code with prettier

* fix: resolve race condition in play tracker test

* fix: log error when fetching now playing data fails

Signed-off-by: Deluan <deluan@navidrome.org>

* feat(ui): refactor Now Playing panel with new components and error handling

Signed-off-by: Deluan <deluan@navidrome.org>

* fix(ui): adjust padding and height in Now Playing panel for improved layout

Signed-off-by: Deluan <deluan@navidrome.org>

* fix(cache): add automatic cleanup to prevent goroutine leak on cache garbage collection

Signed-off-by: Deluan <deluan@navidrome.org>

---------

Signed-off-by: Deluan <deluan@navidrome.org>

ui/src/subsonic/index.js

@@ -54,6 +54,16 @@ const startScan = (options) => httpClient(url('startScan', null, options))
 
 const getScanStatus = () => httpClient(url('getScanStatus'))
 
+const getNowPlaying = () => httpClient(url('getNowPlaying'))
+
+const getAvatarUrl = (username, size) =>
+  baseUrl(
+    url('getAvatar', null, {
+      username,
+      ...(size && { size }),
+    }),
+  )
+
 const getCoverArtUrl = (record, size, square) => {
   const options = {
     ...(record.updatedAt && { _: record.updatedAt }),
@@ -110,7 +120,9 @@ export default {
   setRating,
   startScan,
   getScanStatus,
+  getNowPlaying,
   getCoverArtUrl,
+  getAvatarUrl,
   streamUrl,
   getAlbumInfo,
   getArtistInfo,

ui/src/subsonic/index.test.js

@@ -104,3 +104,26 @@ describe('getCoverArtUrl', () => {
     expect(url).not.toContain('_=')
   })
 })
+
+describe('getAvatarUrl', () => {
+  beforeEach(() => {
+    // Mock localStorage values required by subsonic
+    const localStorageMock = {
+      getItem: vi.fn((key) => {
+        const values = {
+          username: 'testuser',
+          'subsonic-token': 'testtoken',
+          'subsonic-salt': 'testsalt',
+        }
+        return values[key] || null
+      }),
+    }
+    Object.defineProperty(window, 'localStorage', { value: localStorageMock })
+  })
+
+  it('should include username parameter', () => {
+    const url = subsonic.getAvatarUrl('john')
+    expect(url).toContain('getAvatar')
+    expect(url).toContain('username=john')
+  })
+})