feat: Search results page, gapless removal, UI polish (v1.0.11)

- Add full search results page (/search?q=) with artist, album, song sections
- Fix search results column alignment (fixed-width Format column eliminates per-grid auto-sizing variance)
- Remove experimental gapless playback (caused song skipping and beginning cutoffs)
- Add known limitations to README and CHANGELOG (seeking, DnD reliability)
- Update GitHub Actions to Node.js 24 (checkout@v5, setup-node@v5)
- Add align-items: center to tracklist-header CSS

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/App.tsx

@@ -23,6 +23,7 @@ import Statistics from './pages/Statistics';
 import Playlists from './pages/Playlists';
 import Help from './pages/Help';
 import RandomAlbums from './pages/RandomAlbums';
+import SearchResults from './pages/SearchResults';
 import FullscreenPlayer from './components/FullscreenPlayer';
 import ContextMenu from './components/ContextMenu';
 import { useAuthStore } from './store/authStore';
@@ -137,6 +138,7 @@ function AppShell() {
             <Route path="/random-mix" element={<RandomMix />} />
             <Route path="/playlists" element={<Playlists />} />
             <Route path="/label/:name" element={<LabelAlbums />} />
+            <Route path="/search" element={<SearchResults />} />
             <Route path="/statistics" element={<Statistics />} />
             <Route path="/settings" element={<Settings />} />
             <Route path="/help" element={<Help />} />