feat(Moderation): enhance moderation reporting and user feedback

- Added user blocking checks in authentication and reporting processes, returning appropriate error responses.
- Expanded moderation report functionality to include new target types and optional fields for reports.
- Implemented a new API endpoint to retrieve the count of open moderation reports.
- Enhanced frontend components to allow users to report profiles, images, and guestbook entries, with corresponding UI updates.
- Updated internationalization files to include new strings for reporting features in both German and English.

frontend/src/i18n/locales/en/navigation.json

@@ -67,6 +67,7 @@
         "m-administration": {
             "contactrequests": "Contact requests",
             "moderationReports": "Moderation reports",
+            "moderationBadgeTitle": "Open moderation reports",
             "users": "Users",
             "userrights": "User rights",
             "m-users": {