- Rename milestone from 'Features & Extensibility' to 'Multi-Library Support'
- Replace old phases 10-14 (TAG/SMRT/GAP/MB/LAYOUT/PLUG) with 20 multi-library requirements (LIB/LSCAN/VIEW/PLAY/DATA)
- Move deferred features to Future Requirements
- Update research files with multi-library research (Stack, Features, Architecture, Pitfalls)
- Architecture: hybrid model (library_id on audio_files only), libraries in DB, sequential scanning, phantom tracks
- SUMMARY.md with task commits and deviation documentation
- STATE.md advanced to Plan 5 of 5 (80% complete)
- ROADMAP.md updated with 4/5 plans progress
- Requirements KEY-02 and KEY-03 marked complete
- Create 09-02-SUMMARY.md with execution metrics and decisions
- Update STATE.md: advance to plan 3, record metrics
- Mark KEY-01, KEY-04, KEY-05 requirements complete
- Create 09-01-SUMMARY.md with execution metrics and decisions
- Update STATE.md with plan progress and session continuity
- Update ROADMAP.md: mark 09-01 plan complete
- Mark SCAN-01, SCAN-02, SCAN-03 requirements complete
yonlu