feat: add Dolby audio codecs (ac-3, ec-3)

src/model/mod.rs

@@ -343,6 +343,12 @@ pub enum AudioCodec {
     Mp4a,
     /// Opus: <https://en.wikipedia.org/wiki/Opus_(audio_format)>
     Opus,
+    /// Dolby Digital / AC-3: <https://en.wikipedia.org/wiki/Dolby_Digital>
+    #[serde(rename = "ac-3")]
+    Ac3,
+    /// Dolby Digital Plus / EC-3: <https://en.wikipedia.org/wiki/Dolby_Digital_Plus>
+    #[serde(rename = "ec-3")]
+    Ec3,
 }
 
 /// Video file type

src/param/stream_filter.rs

@@ -169,6 +169,8 @@ impl StreamFilter {
             AudioCodec::Unknown => -10,
             AudioCodec::Mp4a => 0,
             AudioCodec::Opus => 10,
+            AudioCodec::Ac3 => 20,
+            AudioCodec::Ec3 => 25,
         };
 
         let language = if self.audio_languages.is_empty() {