feat: finish register receiving and authority routing

Assistant: codex
Assistant-Model: gpt-5.6-sol
Assistant-Session: 01a023c0-a0a3-7c03-b395-5a0d2757214d

docs/adr-003-projection-ui-ownership.md

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+---
+id: RMGR-ADR-003
+type: architecture-decision-record
+title: "Projection UI ownership stays outside Repo Manager"
+status: accepted
+decided: "2026-08-21"
+deciders: ["Repo Manager and hub-core architecture"]
+related:
+  - RMGR-WP-0008
+  - HUB-WP-0004
+  - SHR-ARCH-HUB-0001
+---
+
+# ADR-003: Projection UI ownership stays outside Repo Manager
+
+## Status
+
+**Accepted** (2026-08-21).
+
+## Context
+
+The State Hub retirement inventory initially assigned slice A4's work and
+repository pages to Repo Manager because Repo Manager owns the underlying
+file-backed records. That assignment conflated authority with presentation.
+Repo Manager is a functional component with governed CLI and adapter surfaces;
+it is not a cross-repository hub or dashboard runtime.
+
+The accepted `HUB-WP-0004` architecture keeps repository work authoritative in
+Git through Repo Manager and assigns projection/query and hub UI capabilities
+to hub-core and its operator clients. Building another dashboard here would
+duplicate those projections and blur the one-authority boundary.
+
+## Decision
+
+1. Repo Manager owns repository observation, governed file-backed mutation,
+   reconciliation, indexes, and stable machine-facing contracts. It does not
+   own a dashboard or general operator UI.
+2. hub-core owns cross-repository projection/query contracts and the surviving
+   hub UI runtime. Ops or domain clients may render narrower views through
+   those contracts.
+3. User interfaces consume Repo Manager and hub-core ports. They do not write
+   repository authority or projection storage directly.
+4. State Hub retirement slice A4 is therefore a hub-core/projection-client
+   replacement, not a UI migration into Repo Manager. Repo Manager's A1–A3 and
+   A5 contracts remain inputs to those projections.
+
+## Consequences
+
+RMGR-WP-0008 does not need a dashboard deliverable. A4 route redirects and UI
+replacement remain in the retirement program's hub-core cutover work. Any
+future repository-local UI must be proposed separately and remain a client of
+the same governed contracts.