Fix dropped conversation + add configurable voice volume

Bump version to 0.2.0 so the robot picks up the new build

Add Claude conversation mode: STT → LLM → TTS multi-turn chat, DoA head tracking, antenna-press exit

Fix timezone: use Europe/Berlin (MESZ)

Switch to edge-tts neural voice + gestures while speaking

Use piper-tts neural TTS for natural German voice

Initial commit