feat(ffmpeg): add WAV format support and detection for use in dev mode

- Added WAV format to customFormats with appropriate metadata.
- Implemented detection for RIFF/WAVE format in detectAudioFormat function.

js/ffmpegFormats.ts

@@ -130,6 +130,18 @@ export const customFormats: Record<string, CustomFormat> = {
     },
 };
 
+// Add wav to custom formats when vite is in dev mode
+if (import.meta.env.DEV) {
+    customFormats.FFMPEG_WAV = {
+        displayName: 'WAV (16-bit PCM)',
+        ffmpegArgs: ['-map_metadata', '-1'],
+        outputFilename: 'output.wav',
+        outputMime: 'audio/wav',
+        extension: 'wav',
+        category: 'WAV',
+    };
+}
+
 /**
  * Container format definitions for lossless re-muxing.  Each entry describes
  * the ffmpeg arguments needed to produce that container and provides a

js/utils.js

@@ -140,6 +140,22 @@ export const detectAudioFormat = (view, mimeType = '') => {
         return 'mp3';
     }
 
+    // Detect RIFF/WAVE by "RIFF" at offset 0 and "WAVE" at offset 8 (only in dev mode)
+    if (
+        import.meta.env.DEV &&
+        view.byteLength >= 12 &&
+        view.getUint8(0) === 0x52 && // R
+        view.getUint8(1) === 0x49 && // I
+        view.getUint8(2) === 0x46 && // F
+        view.getUint8(3) === 0x46 && // F
+        view.getUint8(8) === 0x57 && // W
+        view.getUint8(9) === 0x41 && // A
+        view.getUint8(10) === 0x56 && // V
+        view.getUint8(11) === 0x45 // E
+    ) {
+        return 'wav';
+    }
+
     // Check for MPEG frame sync (0xFF 0xFB or 0xFF 0xFA)
     if (view.byteLength >= 2 && view.getUint8(0) === 0xff && (view.getUint8(1) & 0xe0) === 0xe0) {
         return 'mp3';