fix: harden booking and meeting flows

collections/Events.ts

@@ -3,6 +3,7 @@ import { isAdmin, isAdminFieldLevel, publishedOrAdmin } from "@/access";
 import { slugField } from "@/fields/slug";
 import { seoFields } from "@/fields/seo";
 import { generateMeetingPassword } from "@/lib/meeting/password";
+import { revokeChangedMeeting } from "@/lib/meeting/revoke";
 
 export const EVENT_CATEGORIES = [
   { label: "Prozessbegleitung", value: "prozessbegleitung" },
@@ -18,9 +19,9 @@ export const EVENT_CATEGORIES = [
 // Auto-generates the meeting password for new online events, and
 // regenerates it whenever the admin ticks "Neues Passwort generieren".
 // Never derived from the event id/slug — always a fresh random value.
-const setMeetingPassword: CollectionBeforeChangeHook = ({ data }) => {
-  if (!data?.isOnline) return data;
-  if (!data.meetingPassword || data.regeneratePassword) {
+const setMeetingPassword: CollectionBeforeChangeHook = ({ data, originalDoc }) => {
+  if (!(data.isOnline ?? originalDoc?.isOnline)) return data;
+  if (!(data.meetingPassword ?? originalDoc?.meetingPassword) || data.regeneratePassword || originalDoc?.isOnline === false) {
     data.meetingPassword = generateMeetingPassword();
   }
   data.regeneratePassword = false;
@@ -52,6 +53,7 @@ export const Events: CollectionConfig = {
   },
   hooks: {
     beforeChange: [setMeetingPassword],
+    afterChange: [revokeChangedMeeting],
   },
   fields: [
     {