fix: update supported audio formats

.alacs don't exist in the wild, you'd only find them as .m4a
amr can only be converted from, not to (need to build ffmpeg with the encoder)

src/lib/converters/ffmpeg.svelte.ts

@@ -21,9 +21,8 @@ export class FFmpegConverter extends Converter {
 		new FormatInfo("m4a"),
 		...videoFormats.map((f) => new FormatInfo(f, true, true, false)),
 		new FormatInfo("wma"),
-		new FormatInfo("amr"),
+		new FormatInfo("amr", true, false),
 		new FormatInfo("ac3"),
-		new FormatInfo("alac"),
 		new FormatInfo("aiff"),
 	];