audio.cpp 0.5 adds DramaBox expressive TTS, Confucius4 and 7 more models

Release 0.5 ships 9 new TTS models led by DramaBox, a prompt-directed voice-acting model built on the LTX-2.3 audio architecture, plus Confucius4 cross-lingual voice transfer and ROCm/HIP support. Prompts can control emotion, delivery, laughs, sighs, pauses, and speaker behavior.