Detach card assignments atomically when a user deactivates

[Chris0Jeky]

Deactivating a user previously left that user assigned to cards. Self-deactivation now stages assignment removal and audit entries inside the account-state transaction, including archived cards and boards. Other assignees and board ownership/membership stay intact. Cache invalidation and card-assignment notifications happen only after commit; reactivation does not recreate assignments.

Validation:

• Eight new Application cases pass for cleanup, ordering, missing users, detach/save/commit failures, reactivation and post-commit notification failure.
• Four real SQLite API cases pass for active/archived cleanup, other-assignee preservation, unauthorized/foreign requests, rollback after SQL save, and a separate observer seeing committed cleanup before the first notification. Detail/export/audit and queued webhook checks are included.
• Full backend qualification at 6dfa495: 9,746 passed, 34 existing skips, zero failures across six projects. This preserves author source80803b227c70f28d0682c2c8462508b5490d4317 and main9a8c14c6b. Native log and TRX receipts are under C:/td0912-evidence/deactivation-full-backend-trx.
• Independent source review is clean. Original required run34718304809 passed before typed-relations delivery advanced main; the product recovery integration supplies the next combined-base qualification. No final-current-base CI claim is made here.

The original author's missing SDK limitation is superseded by these local executable results. This direct notification path still has a commit-to-notification window; the separate proposal webhook change does not make deactivation a durable outbox path. No process-kill, live SignalR, external HTTP or real concurrent-writer acceptance is claimed. OUTSTANDING_TASKS.md retains all 41 open human actions.

Closes #3000

[Chris0Jeky]

@codex review

Please review the transaction/save/commit/notification boundary, self-scoped actor provenance, required service dependency and the failure-after-SQL-save test. No local .NET pass is claimed; exact-head hosted application/API qualification is required. The documented direct-deactivation commit-to-webhook gap is intentionally not conflated with the separate proposal outbox work.

[chatgpt-codex-connector]

Codex Review: Didn't find any major issues. Chef's kiss.

Reviewed commit: 80803b227c

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[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-09-12T21:43:04.854430Z	80803b2	Draft marked ready

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