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.

backend/services/authService.js

@@ -105,6 +105,9 @@ export const loginUser = async ({ username, password }) => {
     if (!user) {
         throw new Error('credentialsinvalid');
     }
+    if (!user.active) {
+        throw new Error('userblocked');
+    }
     const match = await bcrypt.compare(password, user.password);
     if (!match) {
         throw new Error('credentialsinvalid');