feat(all): add CustomEvents types to components that emit events (#23956)

resolves #22925

BREAKING CHANGE: The `RadioChangeEventDetail` interface has been removed in favor of `RadioGroupChangeEventDetail`.

core/src/components/datetime/datetime-interface.ts

@@ -6,6 +6,11 @@ export interface DatetimeChangeEventDetail {
   value?: string | null;
 }
 
+export interface DatetimeCustomEvent extends CustomEvent {
+  detail: DatetimeChangeEventDetail;
+  target: HTMLIonDatetimeElement;
+}
+
 export interface DatetimeParts {
   month: number;
   day: number | null;