Why: branches merged into main had left their task cards open; backfill status and archive to prevent bookkeeping debt. Evidence: feature-fast-slow-display-design.md(PR#451) feature-fast-slow-display-u1.md(PR#452) feature-svc-account-durability-plan.md(PR#469) fix-surface-list-hydrate.md(PR#454) — merges verified via git log --merges against origin/main. Impact: .task/*.md moved to .task/archive/ with status backfilled; no code or submodule change. Refs: task.sh close (card-autoclose-r1)