feat(speech): switch mentor TTS voice to female diana

Code-only commit; production deployment handled separately.

backend/ruoyi-modules/ruoyi-aihr/src/main/java/org/dromara/aihr/service/AihrSpeechService.java

@@ -36,12 +36,12 @@ public class AihrSpeechService {
     private static final String DEFAULT_TTS_VOICE = "anna";
     private static final Pattern SAFE_VOICE = Pattern.compile("[A-Za-z0-9_./:-]{1,200}");
     private static final Map<String, String> ROLE_VOICES = Map.of(
-        "mentor", "benjamin",
+        "mentor", "diana",
         "customer", "bella",
         "interviewer", "alex"
     );
     private static final Map<String, String> EMOTION_PROMPTS = Map.of(
-        "warm", "请用沉稳、耐心、有经验的老师傅语气说",
+        "warm", "请用温和、耐心、有经验的师傅语气说",
         "professional", "请用沉稳、专业、清晰的语气说",
         "serious", "请用严肃、克制、带明显质疑的语气说",
         "intense", "请用情绪强烈、急切、有压力且明显不满的语气说",

backend/ruoyi-modules/ruoyi-aihr/src/test/java/org/dromara/aihr/service/AihrSpeechServiceTest.java

@@ -32,9 +32,9 @@ class AihrSpeechServiceTest {
         var legacy = AihrSpeechService.buildRequestBody(
             mapper, runtime, "普通播报", "alex", null);
 
-        assertEquals("FunAudioLLM/CosyVoice2-0.5B:benjamin", mentor.path("voice").asText());
+        assertEquals("FunAudioLLM/CosyVoice2-0.5B:diana", mentor.path("voice").asText());
         assertEquals(0.92, mentor.path("speed").asDouble());
-        assertTrue(mentor.path("input").asText().contains("老师傅语气"));
+        assertTrue(mentor.path("input").asText().contains("师傅语气"));
         assertEquals("FunAudioLLM/CosyVoice2-0.5B:bella", customer.path("voice").asText());
         assertEquals(1.3, customer.path("speed").asDouble());
         assertTrue(customer.path("input").asText().contains("情绪强烈"));