Fix kokoro langauge code

mcp_host/tts/hf_zero_gpu_tts.py

@@ -56,7 +56,7 @@ def stream_text_to_speech(
         raise ValueError(f"Voice '{voice}' is not available.")
     
     kokoro_lang = voice[0]
-    standard_lang_code = KOKORO_TO_STD_LANG.get(kokoro_lang, "en")
+    standard_lang_code = KOKORO_TO_STD_LANG[kokoro_lang]
     pipe = pipes[kokoro_lang]
 
     for text in generate_sentences(text_stream, language=standard_lang_code):

mcp_host/tts/utils.py

@@ -30,13 +30,13 @@ VOICES = {
 }
 
 KOKORO_TO_STD_LANG = {
-    "a": "en",
-    "b": "en",
+    "a": "en-us",
+    "b": "en-gb",
     "e": "es",
-    "f": "fr",
+    "f": "fr-fr",
     "h": "hi",
     "i": "it",
+    "p": "pt-br",
     "j": "ja",
-    "p": "pt",
     "z": "zh",
-}
+}