调整音色/语速; add 环境变量;

.env

@@ -0,0 +1,2 @@
+VITE_AZURE_SPEECH_KEY=5b401f52c9064cec9247f4190cf99ea4
+VITE_AZURE_SPEECH_REGION=eastasia

src/views/Editor/EnglishSpeaking/services/speechService.ts

@@ -3,10 +3,10 @@ const REGION = import.meta.env.VITE_AZURE_SPEECH_REGION as string | undefined
 // 美式男声,口齿清晰、随和。备选(都是 en-US-*Neural):
 //   GuyNeural / AndrewNeural / ChristopherNeural / TonyNeural(男)
 //   JennyNeural / EmmaNeural / AvaNeural(女,清晰度也高)
-const VOICE = 'en-US-DavisNeural'
+const VOICE = 'en-US-JennyNeural'
 const FORMAT = 'audio-24khz-48kbitrate-mono-mp3'
 // 默认偏自然偏快;调慢改 -10%、调更快改 +25% 之类。
-const RATE = '+15%'
+const RATE = '+10%'
 
 /**
  * Synthesize English text via Azure Speech REST.