Make CONSTITUTION/AGENTS/STANDARDS framework-owned (overwritten on upgrade) while
never losing user data:
- FRAMEWORK_OWNED vs USER_SEEDED lists (append-friendly per Lead's ask)
- reconcile_framework_files: overwrite framework-owned from defaults/, backing up a
divergent copy ONCE to <file>.pre-constitution.bak (advisory); seed-if-absent for
USER_SEEDED (TOOLS.md)
- anchor rsync preserve excludes to top-level (/<file>) so defaults/<file> still syncs
- never delete *.pre-constitution.bak across upgrades (rsync + cp-fallback)
- snapshot -> sync -> restore-on-failure (ERR/INT/TERM trap) for crash safety
- FRAMEWORK_VERSION 2 -> 3 + v2->v3 migration advisory
- MOSAIC_SYNC_ONLY hook for testability (file phase only, no env side effects)
Fixture suite (test-install-migration.sh) green 7/7: fresh, legacy-edited AGENTS
(overwrite + backup + SOUL/creds survive + idempotent .bak), tuned STANDARDS,
no-TTY, failure-path data integrity. Two real bugs caught + fixed by the fixtures
(unanchored exclude blocking the overwrite; backup deletion on re-upgrade).
file-adapter.ts TS parity + the vitest fixture matrix land in P4 (2/2).
Refs #542
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
