feat: structured data, graph preview and primary category in the SEO tab

- E8 golem15-seo-schema: the type per content kind, the Service grid with
  price and currency checks, custom JSON-LD with a 300 ms parse status
- E9 golem15-seo-graph: nodes and findings from the seo_graph action, the
  JSON, the Rich Results Test link, 800 ms re-check on fill changes, the
  ML locale switch, one queued request, the failure line
- golem15-seo-parent: the primary category select over the record's
  parents; the seoparent Decode accepts the loaded value sent back
- the rebuilt element bundle and vitest smoke tests

classes/field_types.go

@@ -177,7 +177,12 @@ func decodeSchema(app func() *backpack.App) func(context.Context, pact.FormField
 // parents as <type>:<id>.
 func decodeParent(app func() *backpack.App) func(context.Context, pact.FormFieldValue) (pact.FormFieldDecoded, error) {
 	return func(ctx context.Context, in pact.FormFieldValue) (pact.FormFieldDecoded, error) {
-		raw, ok := stringValue(in.Value)
+		value := in.Value
+		if m, isMap := value.(map[string]any); isMap {
+			// The loaded {selected, options} sent back unchanged.
+			value = m["selected"]
+		}
+		raw, ok := stringValue(value)
 		raw = strings.TrimSpace(raw)
 		if !ok {
 			return pact.FormFieldDecoded{}, &pact.FormFieldError{Messages: []string{"golem15.seo::lang.api.value_invalid"}}