feat(10.1-01): run registered widget actions through a cabana-owned route

- pact: AdminClientAssets, AdminAction, AdminActionInput, AdminActionResult,
  HasAdminActions and AdminPartialData contracts
- fields.yaml type: widget with widget, action and fill keys; boot checks the
  plugin tag prefix, the registered action and writable scalar fill fields
- POST .../widgets/{field} behind requireAjax, controller and action
  permissions, scoped non-locking record read and a server-side fill filter
- typed OpenAPI operation, inventories and an acme conformance case

modules/cabana/messages.go

@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"reflect"
 	"sort"
+	"strings"
 
 	"git.golem15.com/golem15/summercms/modules/phrasebook"
 )
@@ -240,6 +241,18 @@ func validateMessageKeys(reg *Registry, tr *phrasebook.Translator) error {
 				return err
 			}
 		}
+		actionNames := make([]string, 0, len(cc.Actions))
+		for name := range cc.Actions {
+			actionNames = append(actionNames, name)
+		}
+		sort.Strings(actionNames)
+		for _, name := range actionNames {
+			// A label with a namespace separator is a phrase key and must
+			// resolve; anything else is literal button text.
+			if label := cc.Actions[name].Label; strings.Contains(label, "::") && !tr.Has(label) {
+				return fmt.Errorf("cabana: admin controller %s/%s: action %s label names missing phrase key %s", cc.PluginID, id, name, label)
+			}
+		}
 		names := make([]string, 0, len(cc.Relations))
 		for name := range cc.Relations {
 			names = append(names, name)