feat:mp3 (#3)

---------

Co-authored-by: intelligence <intelligence@debian.local>
Reviewed-on: #3

macos/Sources/Transui/TranscriptionClient.swift

@@ -146,8 +146,8 @@ struct TranscriptionClient {
     if !model.isEmpty { field("model", model) }
     if !prompt.isEmpty { field("prompt", prompt) }
     data.append("--\(boundary)\r\n")
-    data.append("Content-Disposition: form-data; name=\"file\"; filename=\"recording.wav\"\r\n")
-    data.append("Content-Type: audio/wav\r\n\r\n")
+    data.append("Content-Disposition: form-data; name=\"file\"; filename=\"recording.mp3\"\r\n")
+    data.append("Content-Type: audio/mpeg\r\n\r\n")
     data.append(try Data(contentsOf: recording))
     data.append("\r\n--\(boundary)--\r\n")
     return data