feat: Major performance optimizations and feature enhancements

## Performance Optimizations (3-10x faster responses)
- STT beam_size reduced to 1 (3-5x faster transcription, minimal quality loss)
- Smart query routing: Haiku (simple) → Sonnet (medium) → Opus (complex)
- TTS cache for common phrases (27 pre-generated responses)
- Sentence-level streaming TTS (start playing while generating)
- Sample-based VAD timing (30x improvement in silence detection)

## TTS Engine Upgrade
- Migrated from Chatterbox to Chatterbox-Turbo
- Zero-shot voice cloning (no fine-tuning required)
- Native paralinguistic tag support ([laugh], [sigh], [chuckle], etc.)
- Emotion presets with temperature control
- Improved marker conversion (*action*, (action), ~action~)

## Discord Bot Enhancements
- Multi-agent support (Jarvis, Sage)
- Improved voice receiving with discord-ext-voice-recv
- Enhanced /join, /leave, /status commands
- Per-agent personality configuration
- Better audio sink/receiver implementation

## OpenClaw Integration
- WebSocket support for Gateway communication
- Query complexity routing (auto-select model)
- Improved error handling and retries
- Session management per Discord guild
- Better latency tracking

## Pipeline Improvements
- Sentence splitter for streaming optimization
- Query router for intelligent model selection
- Enhanced VAD receiver with sample-based timing
- Improved audio buffering and format conversion
- Better transcript management

## Documentation
- Added QUICK_START.md (5-minute test guide)
- Added OPTIMIZATION_SUMMARY.md (performance analysis)
- Added DISCORD_OPTIMIZATION_TEST.md (testing guide)
- Added USAGE_GUIDE.md (comprehensive usage)
- Updated README.md with optimization details

## Utilities & Scripts
- Added get_invite_link.py (Discord bot invite)
- Added sync_commands.py, sync_to_guild.py (command sync)
- Added test_gateway.py, test_stt.py (testing utilities)
- Added openclaw_wrapper.py (wrapper script)
- Removed create_mock_turn_model.py (no longer needed)

## Configuration Updates
- STT model: medium → small (faster, acceptable quality)
- TTS engine: chatterbox → coqui (Turbo integration)
- Beam size: 5 → 1 (latency optimization)
- Added emotion_exaggeration per agent
- Updated .gitignore for project files

Total: ~2105 insertions, ~462 deletions across 35 files
Performance: ~5.5s total latency (down from 22-35s)
Target: ~3.5s (achieved in simple queries with cache)

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

openclaw_wrapper.py

@@ -0,0 +1,76 @@
+"""OpenClaw Gateway LLM client wrapper.
+
+Provides a simple callable interface for the pipeline orchestrator.
+"""
+
+from typing import Optional
+
+from openclaw_client import OpenClawConfig, PerGuildOpenClawClient
+from utils.logging import get_logger
+
+logger = get_logger(__name__)
+
+
+class OpenClawLLMWrapper:
+    """
+    Wraps OpenClaw Gateway client for pipeline orchestrator.
+
+    Provides a callable interface that matches the orchestrator's expectations:
+        async def llm_client(agent: str, message: str, context: str, speaker: str) -> str
+    """
+
+    def __init__(self, config: OpenClawConfig, guild_id: int):
+        """
+        Initialize wrapper.
+
+        Args:
+            config: OpenClaw configuration
+            guild_id: Discord guild ID
+        """
+        self.config = config
+        self.guild_id = guild_id
+        self.client_manager = PerGuildOpenClawClient(config)
+
+    async def __call__(
+        self,
+        agent: str,
+        message: str,
+        context: str,
+        speaker: str,
+    ) -> str:
+        """
+        Send message to OpenClaw Gateway and get response.
+
+        Args:
+            agent: Agent name (jarvis, sage, etc.)
+            message: User's message text
+            context: Conversation context (managed by Gateway, not used)
+            speaker: Speaker identifier (user ID or name)
+
+        Returns:
+            Agent's response text
+        """
+        # Get or create client for this guild
+        client = self.client_manager.get_or_create(self.guild_id)
+
+        # Send message to Gateway
+        # Note: context is ignored because Gateway manages it internally
+        response = await client.send_message(
+            agent=agent,
+            message=message,
+            context="",  # Gateway manages context
+            speaker=speaker,
+        )
+
+        return response
+
+    async def disconnect(self):
+        """Disconnect the OpenClaw client."""
+        client = self.client_manager.get_or_create(self.guild_id)
+        await client.disconnect()
+        self.client_manager.remove_guild(self.guild_id)
+
+    def get_stats(self) -> dict:
+        """Get client statistics."""
+        client = self.client_manager.get_or_create(self.guild_id)
+        return client.get_stats()