REUSE-WP-0014: T10 hub sync and federation dedup plan

Sync 60 hub URL sources, compose federated index (37 capabilities).
Document owner-migration collision policy and per-owner removal plan.

docs/RegistryFederation.md

@@ -159,6 +159,27 @@ remote sources without cache fail compose with a clear error.
 `warn` (default): duplicate IDs across sources are kept but reported as
 warnings. Consumers must inspect `source_repo` before choosing an entry.
 
+### Owner migration and deduplication
+
+After REUSE-WP-0014, many capabilities remain in both `reuse-surface` and their
+`owner` repo index (seeded from reuse-surface during establishment). Federation
+compose warns on these duplicates; it does **not** merge or prefer one source.
+
+| Rule | Behavior |
+|---|---|
+| Canonical owner | The repo named in the entry `owner` field |
+| Federation winner | Consumers pick the row where `source_repo` matches `owner` |
+| reuse-surface copies | Planning stubs until owner index is published and fetchable |
+| Removal | Separate commit per owner in `reuse-surface` — see `history/2026-06-16-federation-deduplication-plan.md` |
+| Blocked owners | Keep reuse-surface row while owner `publish_check` fails (Gitea 404) |
+
+Workstation rollout status: `registry/federation/local-repo-roster.yaml` (60 local
+repos, publish pass/fail per slug).
+
+Post-rollout compose (2026-06-16): **60** hub-synced URL sources, **37** federated
+capability rows, **16** duplicate-ID warnings (mostly owner-migrated entries still
+listed in reuse-surface).
+
 ## Hosted federation hub
 
 Production hub: **`https://reuse.coulomb.social`** (Railiance `railiance01`,