Adds tool-agnostic AGENTS.md as canonical context file, CLAUDE.md symlink for Claude Code compatibility, and docs/templates/ with spec.md + adr.md. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
- DB: stems table with trackId FK, fileKey, sortOrder, createdById - API: GET/POST/DELETE stems, presigned upload URL, ZIP download via fflate - Web: StemUploadDropzone (multi-file, batch upload, progress bars) - Web: StemList with download-all-ZIP and per-stem delete - Web: STEMs tab in track detail view - Icon: add 'music' icon to inline set - Auto-migration runs stems table creation on boot Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
