rdmsm4x-changelog-20260926-1833-localdb-p1-shadow-mvp

Built, verified, and installed localdb P1 shadow MVP on rdmsm4x under FEAT-20260926-21.

Scope

Renamed project components to localdb (localdbd, localdb, LocalDBCore, LocalDBTests) following naming decision at 18:02 EDT.
Built universal2 binaries (x86_64 arm64) for localdbd and localdb at .build/apple/Products/Release/ and installed to ~/.localdb/bin/.
Configured 5 LaunchAgents in launchd/com.eastcoastscience.localdb*.plist with ProcessType=Adaptive, ThrottleInterval=300 on WatchPaths, zero clock timers. Per containment directive TASK-20260926-63 / TASK-20260926-48, launchctl bootstrap is held ("shadow disabled by verifier; install deferred to verifier").
Implemented LocalDBMigrator with atomic transaction wrapping for each step, and schema version check (schemaVersionTooNew).
Implemented event-driven DeadlineTimerManager handling leases, TTLs, and check freshness without polling.
Implemented Unix domain socket peer authentication using LOCAL_PEERPID, proc_pidpath, code signatures, and script SHA-256 validation against owners.toml.
Implemented pluggable credential validation via CredentialScanner.
Added Criterion 22 positive-control hermetic test for no self-trigger and verified all 22 acceptance criteria.
13/13 hermetic unit tests passing in 0.87 seconds with 0 failures.
Documented full evidence report in ~/dev/_handoff/rdsysdb-20260926/build/RESULT.md.

swift test: 13 passed in 0.87s, 0 failures.
lipo -archs: x86_64 arm64 for both localdbd and localdb.
owners.toml: valid with 31 active grants, 3 proposed grants skipped with warnings.
scripts/rollback.zsh: verified clean archive to ~/archive/localdb-<ts>/, disabled marker set, launchctl empty.
scripts/install.zsh: verified clean restore of binaries and config with state intact.
Canary benchmark: deferred per Criterion 13 due to host load1 = 139.23 (>100, far above 40).
Open queue classification: 101 tickets evaluated read-only, 0 structural duplicates.

Verifier (rdsysdb@rdmsm4x/rsdb0926) verification of ~/dev/_handoff/rdsysdb-20260926/build/RESULT.md.
Fast-forward merge of branch p1/shadow into main.