REUSE-WP-0019-T03: add Forgejo Actions workflows (part 2 of prior commit)

The .forgejo/workflows/ files and doc updates described in 4862ed6 didn't
actually get staged there (git add silently skipped them after an earlier
pathspec miss on the already-deleted .gitea file) -- committing them now.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

SCOPE.md

@@ -80,6 +80,11 @@ The MVP registry foundation, CLI tooling (REUSE-WP-0003), federation stack
   get a reuse/extend/new verdict; `--file-request` bridges a `new` verdict to
   a State Hub capability request; `report gaps --check-capability-requests`
   surfaces open requests with no matching capability
+- **Get automatic hub refresh** (REUSE-WP-0019-T02) — a Forgejo push
+  webhook (`POST /v1/webhooks/forgejo`, HMAC-signed) recomposes the hub's
+  federated index when a registered repo's `registry/indexes/` changes,
+  with `composed_at`/`stale` visibility on `GET /v1/federated` and a
+  scheduled fallback recompose if a webhook delivery is ever missed
 
 Registry **tooling** availability is **A4** (CLI plus hosted hub HTTP API).
 Registry **authoring** remains Markdown-first; consumption combines entries, the
@@ -87,9 +92,6 @@ index, CLI automation, and the production hub.
 
 ## What Is Not Possible Yet
 
-- **Automatic hub refresh** — federated compose is on-demand; no polling or
-  webhooks
-
 - **Multi-domain federation** — all indexed capabilities remain `helix_forge`
 - **Planning analytics breadth** — `report gaps` shipped (REUSE-WP-0015-T03);
   no roadmap views or standardization tracker beyond `overlaps` and compose
@@ -123,8 +125,11 @@ See `tools/README.md` for command reference.
 - **Specs:** `specs/FederationHubAPI.md`, `schemas/hub-registration.schema.yaml`.
 - **Docs:** `docs/CapabilityRegistryConcept.md`, `docs/RegistryFederation.md`,
   `docs/IntentScopeGapAnalysis.md`, deploy guide `docs/deploy/reuse-kubernetes.md`.
-- **CI:** `.gitea/workflows/ci.yml` — validate, federation compose, catalog,
-  graph, pytest, informational `report cohorts`, `stats --roster`, `report gaps`.
+- **CI:** `.forgejo/workflows/ci.yml` — validate, federation compose, catalog,
+  graph, pytest, informational `report cohorts`, `stats --roster`, `report gaps`
+  (migrated from Gitea 2026-07-07, REUSE-WP-0019-T03). Also
+  `.forgejo/workflows/image.yaml` (container build/push) and
+  `recompose-fallback.yaml` (scheduled hub recompose, webhook backstop).
 - **Relation graph:** `docs/graph/capability-graph.mmd`, `docs/graph/index.html`.
 - **Searchable catalog:** `docs/catalog/search.html`.
 - **Workplans:** REUSE-WP-0001 through REUSE-WP-0015 finished (archived);