Add explicit Target Duration slider (0–60s) + gen_duration kwarg

Patch end-of-clip silence prior at latent frame 513 for >20s outputs

Use richer duration estimator in warm server (sentence + non-verbal aware)

Fetch unsloth bnb-4bit Gemma + Dramabox checkpoints from HF on startup

DramaBox Space — initial app + vendored ltx2