refactor: migrate audio metadata tagging from ts to rust

- Add id3 and metaflac crates for native audio tagging
- Create tagger.rs with separate tag_mp3() and tag_flac() functions
- Implement tag_audio_file Tauri command for unified tagging interface
- Support full metadata: title, artist, album, track#, ISRC, BPM, lyrics, cover art
- Create TypeScript wrapper (tagger.ts) for calling Rust backend
- Update downloader.ts to use Rust tagging for both MP3 and FLAC
- Remove browser-id3-writer dependency (no browser FLAC support)
- Inline lyrics parsing in addToQueue.ts (no longer needed in tagger)

src/lib/services/deezer/downloader.ts

@@ -6,7 +6,7 @@ import { fetch } from '@tauri-apps/plugin-http';
 import { writeFile, mkdir, remove, rename, exists } from '@tauri-apps/plugin-fs';
 import { generateBlowfishKey, decryptChunk } from './crypto';
 import { generateTrackPath } from './paths';
-import { tagMP3 } from './tagger';
+import { tagAudioFile } from './tagger';
 import { downloadCover, saveCoverToAlbumFolder } from './imageDownload';
 import { settings } from '$lib/stores/settings';
 import { get } from 'svelte/store';
@@ -106,22 +106,9 @@ export async function downloadTrack(
       }
     }
 
-    // Apply tags (currently MP3 only)
-    let finalData = decryptedData;
-    if (format === 'MP3_320' || format === 'MP3_128') {
-      console.log('Tagging MP3 file...');
-      finalData = await tagMP3(
-        decryptedData,
-        track,
-        appSettings.embedCoverArt ? coverData : undefined,
-        appSettings.embedLyrics
-      );
-    }
-    // TODO: Add FLAC tagging when library is ready
-
-    // Write tagged file to temp
-    console.log('Writing tagged file to temp...');
-    await writeFile(paths.tempPath, finalData);
+    // Write untagged file to temp first
+    console.log('Writing untagged file to temp...');
+    await writeFile(paths.tempPath, decryptedData);
 
     // Move to final location
     const finalPath = `${paths.filepath}/${paths.filename}`;
@@ -135,6 +122,21 @@ export async function downloadTrack(
 
     await rename(paths.tempPath, finalPath);
 
+    // Apply tags (works for both MP3 and FLAC)
+    console.log('Tagging audio file...');
+    try {
+      await tagAudioFile(
+        finalPath,
+        track,
+        appSettings.embedCoverArt ? coverData : undefined,
+        appSettings.embedLyrics
+      );
+      console.log('Tagging complete!');
+    } catch (error) {
+      console.error('Failed to tag audio file:', error);
+      // Non-fatal error - file is still downloaded, just not tagged
+    }
+
     // Save LRC sidecar file if enabled
     if (appSettings.saveLrcFile && track.lyrics?.sync) {
       try {