Why: land the approved review conclusions as a formal proposal, U1/U4
specs, and draft task cards without starting business implementation.
Evidence: SELF precheck READY (receipt in task card); docs-only change.
Impact: planning docs and Documents gitlink; runtime behavior unchanged.
Refs: .task/feature-svc-unified-deploy-login-key.md
Co-authored-by: Cursor <cursoragent@cursor.com>
