Add voice management tool bin/voice_tool.py and dynamic voice switching system

bot.py

@@ -18,6 +18,7 @@ from claude_agent_sdk import ClaudeAgentOptions, SandboxSettings
 from loguru import logger
 
 from brain import Brain
+from voice_manager import VoiceManager
 from claude_llm import ClaudeCodeLLM
 from echo_guard import EchoGuardUserMuteStrategy
 from pipecat.audio.vad.silero import SileroVADAnalyzer
@@ -70,6 +71,7 @@ say them:
 - Spell out things that only make sense visually. Say "line forty-two of
   bot dot py" rather than pasting a path.
 - Use your available tools (listing directories, searching, reading files) whenever the user asks about files or workspace tasks.
+- You can change your own voice! If the user asks to list available voices or switch voice, run `python bin/voice_tool.py list` or `python bin/voice_tool.py set <voice_name>` (voices: af_heart, af_bella, am_michael, am_fenrir, am_puck, bf_emma, bm_george, Moira, Daniel).
 - Complete multi-step tool calls fully before speaking your response. Do not stop halfway to ask if you should continue.
 - Be strictly truthful about your findings and never invent fake file contents.
 - The user's words reach you through speech recognition, so expect occasional
@@ -326,7 +328,7 @@ def build_stt(args: argparse.Namespace, vocabulary):
     return WhisperSTTService(settings=WhisperSTTService.Settings(model=model, language=Language.EN))
 
 
-def build_tts(args: argparse.Namespace):
+def build_tts(args: argparse.Namespace, voice_manager=None):
     if args.tts == "apple":
         from apple_tts import AppleTTSService, find_voice
 
@@ -339,12 +341,15 @@ def build_tts(args: argparse.Namespace):
 
     if args.voice_rate:
         logger.warning("--voice-rate only applies to --tts apple; ignoring it.")
-    voice = args.voice or "af_heart"
+    voice = (voice_manager.load_saved_voice() if voice_manager else None) or args.voice or "af_heart"
     logger.info(f"Text to speech: Kokoro {voice}")
-    return KokoroTTSService(
+    tts = KokoroTTSService(
         settings=KokoroTTSService.Settings(voice=voice, language=Language.EN),
         text_filters=[SpokenTextFilter()],
     )
+    if voice_manager:
+        voice_manager.set_tts_processor(tts)
+    return tts
 
 
 def build_turn_taking(args: argparse.Namespace):
@@ -580,9 +585,9 @@ async def main() -> int:
         if vocabulary:
             vocabulary.observe(text)
 
+    voice_manager = VoiceManager(workspace)
     llm = build_llm(args, vocabulary, brain, observer=on_reply)
-
-    tts = build_tts(args)
+    tts = build_tts(args, voice_manager=voice_manager)
 
     # Claude keeps its own history; this context exists so Pipecat can decide
     # when a turn has ended.