feat(audio): add ALAC and AAC-LC native decoding via Symphonia

Add 'alac' to symphonia features. Combined with the existing 'aac' and
'isomp4' features this enables native lossless decoding of Apple Lossless
Audio Codec (.m4a/ALAC) and AAC-LC files without server-side transcoding.

Symphonia probes the format from the stream bytes, so no URL or hint
changes are needed for server streams.

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

src-tauri/Cargo.lock

@@ -4402,6 +4402,7 @@ dependencies = [
  "symphonia-bundle-mp3",
  "symphonia-codec-aac",
  "symphonia-codec-adpcm",
+ "symphonia-codec-alac",
  "symphonia-codec-pcm",
  "symphonia-codec-vorbis",
  "symphonia-core",
@@ -4456,6 +4457,16 @@ dependencies = [
  "symphonia-core",
 ]
 
+[[package]]
+name = "symphonia-codec-alac"
+version = "0.5.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8413fa754942ac16a73634c9dfd1500ed5c61430956b33728567f667fdd393ab"
+dependencies = [
+ "log",
+ "symphonia-core",
+]
+
 [[package]]
 name = "symphonia-codec-pcm"
 version = "0.5.5"