fix: disable forced resampling to 44100 Hz on first track

current_sample_rate was initialized to 44100, causing every track to be
resampled down to 44.1 kHz. Setting it to 0 disables resampling until
the actual track rate is known, so songs play at their native sample rate.

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

src-tauri/src/audio.rs

@@ -967,7 +967,7 @@ pub fn create_engine() -> (AudioEngine, std::thread::JoinHandle<()>) {
         gapless_enabled: Arc::new(AtomicBool::new(false)),
         chained_info: Arc::new(Mutex::new(None)),
         samples_played: Arc::new(AtomicU64::new(0)),
-        current_sample_rate: Arc::new(AtomicU32::new(44100)),
+        current_sample_rate: Arc::new(AtomicU32::new(0)),
         current_channels: Arc::new(AtomicU32::new(2)),
         gapless_switch_at: Arc::new(AtomicU64::new(0)),
     };