Add audit system, invite links, and usage analytics (#4749)

# Description of Changes

New Features
Audit System: Complete audit logging with dashboard, event tracking, and
export capabilities

Invite Links: Secure invite system with email notifications and
expiration

Usage Analytics: Endpoint usage statistics and visualization

License Management: User counting with grandfathering and license
enforcement
## Checklist

### General

- [ ] I have read the [Contribution
Guidelines](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/CONTRIBUTING.md)
- [ ] I have read the [Stirling-PDF Developer
Guide](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/devGuide/DeveloperGuide.md)
(if applicable)
- [ ] I have read the [How to add new languages to
Stirling-PDF](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/devGuide/HowToAddNewLanguage.md)
(if applicable)
- [ ] I have performed a self-review of my own code
- [ ] My changes generate no new warnings

### Documentation

- [ ] I have updated relevant docs on [Stirling-PDF's doc
repo](https://github.com/Stirling-Tools/Stirling-Tools.github.io/blob/main/docs/)
(if functionality has heavily changed)
- [ ] I have read the section [Add New Translation
Tags](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/devGuide/HowToAddNewLanguage.md#add-new-translation-tags)
(for new translation tags only)

### UI Changes (if applicable)

- [ ] Screenshots or videos demonstrating the UI changes are attached
(e.g., as comments or direct attachments in the PR)

### Testing (if applicable)

- [ ] I have tested my changes locally. Refer to the [Testing
Guide](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/devGuide/DeveloperGuide.md#6-testing)
for more details.

---------

Co-authored-by: James Brunton <[email protected]>

frontend/src/proprietary/routes/Login.tsx

@@ -1,5 +1,5 @@
 import { useEffect, useState } from 'react';
-import { useNavigate } from 'react-router-dom';
+import { useNavigate, useSearchParams } from 'react-router-dom';
 import { springAuth } from '@app/auth/springAuthClient';
 import { useAuth } from '@app/auth/UseSession';
 import { useTranslation } from 'react-i18next';
@@ -17,26 +17,42 @@ import { BASE_PATH } from '@app/constants/app';
 
 export default function Login() {
   const navigate = useNavigate();
+  const [searchParams] = useSearchParams();
   const { session, loading } = useAuth();
   const { t } = useTranslation();
   const [isSigningIn, setIsSigningIn] = useState(false);
   const [error, setError] = useState<string | null>(null);
+  const [successMessage, setSuccessMessage] = useState<string | null>(null);
   const [showEmailForm, setShowEmailForm] = useState(false);
   const [email, setEmail] = useState('');
   const [password, setPassword] = useState('');
 
-  // Prefill email from query param (e.g. after password reset)
+  // Handle query params (email prefill and success messages)
   useEffect(() => {
     try {
-      const url = new URL(window.location.href);
-      const emailFromQuery = url.searchParams.get('email');
+      const emailFromQuery = searchParams.get('email');
       if (emailFromQuery) {
         setEmail(emailFromQuery);
       }
+
+      const messageType = searchParams.get('messageType')
+      if (messageType) {
+        switch (messageType) {
+          case 'accountCreated':
+            setSuccessMessage(t('login.accountCreatedSuccess', 'Account created successfully! You can now sign in.'))
+            break
+          case 'passwordChanged':
+            setSuccessMessage(t('login.passwordChangedSuccess', 'Password changed successfully! Please sign in with your new password.'))
+            break
+          case 'credsUpdated':
+            setSuccessMessage(t('login.credentialsUpdated', 'Your credentials have been updated. Please sign in again.'))
+            break
+        }
+      }
     } catch (_) {
       // ignore
     }
-  }, []);
+  }, [searchParams, t]);
 
   const baseUrl = window.location.origin + BASE_PATH;
 
@@ -121,6 +137,22 @@ export default function Login() {
     <AuthLayout>
       <LoginHeader title={t('login.login') || 'Sign in'} />
 
+      {/* Success message */}
+      {successMessage && (
+        <div style={{
+          padding: '1rem',
+          marginBottom: '1rem',
+          backgroundColor: 'rgba(34, 197, 94, 0.1)',
+          border: '1px solid rgba(34, 197, 94, 0.3)',
+          borderRadius: '0.5rem',
+          color: '#16a34a'
+        }}>
+          <p style={{ margin: 0, fontSize: '0.875rem', textAlign: 'center' }}>
+            {successMessage}
+          </p>
+        </div>
+      )}
+
       <ErrorMessage error={error} />
 
       {/* OAuth first */}