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>