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/http.go

@@ -262,6 +262,7 @@ func constrainNested(g pact.Router) {
 //
 //	GET /{vendor}/{plugin}/{controller}/{id}/relations/{name}
 //	GET /{vendor}/{plugin}/{controller}/fields/{field}/options
+//	GET /{vendor}/{plugin}/{controller}/filters/{scope}/options
 //
 // A numeric id never equals a literal segment, so the dispatch is unambiguous.
 // Anything else is the D-10 not_found envelope, as an unmatched API path.
@@ -271,6 +272,9 @@ func (s *service) nestedGet(w http.ResponseWriter, r *http.Request) {
 	case id == "fields" && name == "options":
 		r.SetPathValue("field", segment)
 		s.fieldOptions(w, r)
+	case id == "filters" && name == "options":
+		r.SetPathValue("scope", segment)
+		s.filterOptions(w, r)
 	case segment == "relations":
 		s.relationLinked(w, r)
 	default: