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

pact/capabilities.go

@@ -262,6 +262,13 @@ type FilterScope interface {
 	FilterScope(name string, db *gorm.DB, value any) *gorm.DB
 }
 
+// FilterOptions serves the choices of a model-backed config_filter scope
+// (D-27). It is implemented by the same model as FilterScope and receives the
+// filter's scope method name; labels may be phrase keys.
+type FilterOptions interface {
+	FilterOptions(scope string) []Option
+}
+
 // HasLang is implemented by plugins that ship embedded translation YAML
 // under lang/<locale>/<group>.yaml.
 type HasLang interface {