feat(10-02): filter choices and a fully typed admin API proven on the wire

- pact.FilterOptions on the model serves a scope filter's choices; a scope
  filter whose model lacks it fails activation (D-27)
- GET /{vendor}/{plugin}/{controller}/filters/{scope}/options answers a
  declared scope filter behind the controller permission with localized
  {value, label} choices, 404 otherwise
- Every admin route documents a typed success schema, and protected routes
  document 401, 403 and 404 (422 on writes); SuccessEnvelope is gone and
  logout writes a typed AdminLogoutData
- jsonScalar and fieldContext decode their served shapes
- TestPhase10OpenAPIConformance calls every inventoried route through the
  assembled router on PostgreSQL and decodes each body into its documented
  type with unknown fields disallowed, checking admin.json's schema ref
- The SPA aliases every new schema type; Tailwind no longer scans the
  generated API files, so API changes do not churn boardwalk/dist

cabana/export_test.go

@@ -0,0 +1,13 @@
+package cabana
+
+// AdminAPIRoutes exposes the admin API route inventory (method plus
+// prefix-relative path) to the external conformance test.
+func AdminAPIRoutes() []string {
+	out := make([]string, 0, len(phase09Routes))
+	for _, route := range phase09Routes {
+		if !route.spa {
+			out = append(out, route.key)
+		}
+	}
+	return out
+}