Config UI: tag filters and complete schema help/labels coverage (#23796)

* Config UI: add tag filters and complete schema help/labels

* Config UI: finalize tags/help polish and unblock test suite

* Protocol: regenerate Swift gateway models

src/channels/plugins/types.plugin.ts

@@ -33,6 +33,7 @@ import type {
 export type ChannelConfigUiHint = {
   label?: string;
   help?: string;
+  tags?: string[];
   advanced?: boolean;
   sensitive?: boolean;
   placeholder?: string;