feat(ui): add advanced controls accordion — inference steps, cfg, infer method, seed, lm cot, schedule, metadata

feat(pipeline): wire cover/extend/edit task_types in studio.generate

fix(pipeline): pass save_dir so generate_music writes a usable file path

refactor(pipeline): rewrite for real acestep AceStepHandler+LLMHandler api

fix(pipeline): correct hf model id to acestep-v15-xl-sft

feat(pipeline): lazy ace-step singleton with device-aware load

chore(fmt): apply ruff format and remove unused import in conftest

feat(pipeline): add device autodetect with mps-safe vram limit