ci / vet-and-test (pull_request) Successful in 41s
Why: the approved plan U3 (KTD3/KTD7/KTD10 plus minimal recovery isolation) requires concurrent submits to not silently overwrite, unknown-side-effect runs to never auto-resume, and the shared rate limiter to degrade conservatively instead of failing open. Evidence: full backend suite green twice-relevant paths against real PostgreSQL 18.6 and Redis (isolated instance) and on SQLite; new tests - card_version_test (concurrent single winner), recovery_hold_test + recovery_holds_test (skip/release/fail-closed CRUD), ratelimit atomic-window and degraded-fallback tests. Impact: AppendMessageWithRequest now allocates seq under the conversation advisory lock in one transaction; activity_cards gain version (v19) with SaveCardVersioned/GetCardVersion/CardVersion and cardsvc user mutations (status/pin/action/resolve-by-ref) return 409-mapped conflicts while system mirrors keep blind writes; recovery_holds (v20) with admin list/release endpoints and fail-closed resume skip; Redis limiter uses one Lua INCR+PEXPIRE script and falls back to a per-instance limit with a Degraded counter. Refs: proposals/2026-10-11-collaboration-storage-and-distribution.md U3 KTD3/KTD7/KTD10; R3/R6/R7/R8.