[Parity remediation in progress] Enhance startup pipeline and optimize photo album management

[OliverZhaohaibin]

Parity remediation in progress — do not merge

PR #890 is retained as the review baseline for head 59c961875a5e337299cf7f2fb1bff59c63b74f93. Its 105 commits / 365 files mixed independent Startup, Detail, Live Photo, Edit, Library, Recognition, Pets, CI, and legacy-removal changes, so it will not be merged or cherry-picked as a whole.

The first #891–#899 split was not fully behaviorally equivalent. In particular, the Detail core existed but the production playback path still bypassed the scheduler/cache/residency path, causing a severe performance regression. The parity remediation below is therefore still active.

Already merged into edit-base

1. #891 — Fix CI routing for edit-base
2. #892 — Harden startup orchestration and shutdown lifecycle
3. #893 — Build bounded Detail decode and cache core
4. #894 — Fix Live Photo motion-to-still presentation lifecycle
5. #895 — Harden Detail/Edit/Library lifecycle
6. #896 — Add recoverable Recognition mutation coordination
7. #897 — Harden Pets recognition contracts and recovery
8. #898 — Remove legacy architecture and finalize lifecycle gates
9. #899 — Restore edit-base runtime initialization contracts

Active parity remediation

1. #900 — Restore GPU-first Detail production integration — draft; three-platform CI and instrumentation-only baseline comparison pending
2. Recognition query and merge services — pending after Restore GPU-first Detail production integration #900 merges
3. Coordinator domain decomposition and lazy feature runtime — pending after the Recognition PR merges

A 105-commit parity ledger is maintained in #900 and will be updated through all three remediation PRs. No #890 behavior may disappear without being marked either “migrated” or “equivalently replaced by a newer implementation.”

#890 remains open and unmerged while remediation is in progress. After all three PRs merge into edit-base, this description will be updated with final validation evidence and #890 will be closed as superseded, not merged.