Fix email invite/ allow non auth and table refresh issues (#5076)

# Description of Changes

- Show warning when email invite fails but user is created
  - Auto-refresh user/team tables after modifications
  - Fix invite email URLs to use frontend URL instead of backend
  - Support anonymous SMTP for local development
---

## 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)

### Translations (if applicable)

- [ ] I ran
[`scripts/counter_translation.py`](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/docs/counter_translation.md)

### 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.

app/proprietary/src/main/java/stirling/software/proprietary/security/configuration/MailConfig.java

@@ -35,15 +35,40 @@ public class MailConfig {
         JavaMailSenderImpl mailSender = new JavaMailSenderImpl();
         mailSender.setHost(mailProperties.getHost());
         mailSender.setPort(mailProperties.getPort());
-        mailSender.setUsername(mailProperties.getUsername());
-        mailSender.setPassword(mailProperties.getPassword());
         mailSender.setDefaultEncoding("UTF-8");
 
+        // Only set username and password if they are provided
+        String username = mailProperties.getUsername();
+        String password = mailProperties.getPassword();
+        boolean hasCredentials =
+                (username != null && !username.trim().isEmpty())
+                        || (password != null && !password.trim().isEmpty());
+
+        if (username != null && !username.trim().isEmpty()) {
+            mailSender.setUsername(username);
+            log.info("SMTP username configured");
+        } else {
+            log.info("SMTP username not configured - using anonymous connection");
+        }
+
+        if (password != null && !password.trim().isEmpty()) {
+            mailSender.setPassword(password);
+            log.info("SMTP password configured");
+        } else {
+            log.info("SMTP password not configured");
+        }
+
         // Retrieves the JavaMail properties to configure additional SMTP parameters
         Properties props = mailSender.getJavaMailProperties();
 
-        // Enables SMTP authentication
-        props.put("mail.smtp.auth", "true");
+        // Only enable SMTP authentication if credentials are provided
+        if (hasCredentials) {
+            props.put("mail.smtp.auth", "true");
+            log.info("SMTP authentication enabled");
+        } else {
+            props.put("mail.smtp.auth", "false");
+            log.info("SMTP authentication disabled - no credentials provided");
+        }
 
         // Enables STARTTLS to encrypt the connection if supported by the SMTP server
         props.put("mail.smtp.starttls.enable", "true");

app/proprietary/src/main/java/stirling/software/proprietary/security/controller/api/UserController.java

@@ -407,7 +407,8 @@ public class UserController {
     public ResponseEntity<?> inviteUsers(
             @RequestParam(name = "emails", required = true) String emails,
             @RequestParam(name = "role", defaultValue = "ROLE_USER") String role,
-            @RequestParam(name = "teamId", required = false) Long teamId)
+            @RequestParam(name = "teamId", required = false) Long teamId,
+            HttpServletRequest request)
             throws SQLException, UnsupportedProviderException {
 
         // Check if email invites are enabled
@@ -477,6 +478,9 @@ public class UserController {
             }
         }
 
+        // Build login URL
+        String loginUrl = buildLoginUrl(request);
+
         int successCount = 0;
         int failureCount = 0;
         StringBuilder errors = new StringBuilder();
@@ -488,7 +492,7 @@ public class UserController {
                 continue;
             }
 
-            InviteResult result = processEmailInvite(email, effectiveTeamId, role);
+            InviteResult result = processEmailInvite(email, effectiveTeamId, role, loginUrl);
             if (result.isSuccess()) {
                 successCount++;
             } else {
@@ -687,15 +691,45 @@ public class UserController {
         return ResponseEntity.ok(apiKey);
     }
 
+    /**
+     * Helper method to build the login URL from the application configuration or request.
+     *
+     * @param request The HTTP request
+     * @return The login URL
+     */
+    private String buildLoginUrl(HttpServletRequest request) {
+        String baseUrl;
+        String configuredFrontendUrl = applicationProperties.getSystem().getFrontendUrl();
+        if (configuredFrontendUrl != null && !configuredFrontendUrl.trim().isEmpty()) {
+            // Use configured frontend URL (remove trailing slash if present)
+            baseUrl =
+                    configuredFrontendUrl.endsWith("/")
+                            ? configuredFrontendUrl.substring(0, configuredFrontendUrl.length() - 1)
+                            : configuredFrontendUrl;
+        } else {
+            // Fall back to backend URL from request
+            baseUrl =
+                    request.getScheme()
+                            + "://"
+                            + request.getServerName()
+                            + (request.getServerPort() != 80 && request.getServerPort() != 443
+                                    ? ":" + request.getServerPort()
+                                    : "");
+        }
+        return baseUrl + "/login";
+    }
+
     /**
      * Helper method to process a single email invitation.
      *
      * @param email The email address to invite
      * @param teamId The team ID to assign the user to
      * @param role The role to assign to the user
+     * @param loginUrl The URL to the login page
      * @return InviteResult containing success status and optional error message
      */
-    private InviteResult processEmailInvite(String email, Long teamId, String role) {
+    private InviteResult processEmailInvite(
+            String email, Long teamId, String role, String loginUrl) {
         try {
             // Validate email format (basic check)
             if (!email.contains("@") || !email.contains(".")) {
@@ -715,7 +749,7 @@ public class UserController {
 
             // Send invite email
             try {
-                emailService.get().sendInviteEmail(email, email, temporaryPassword);
+                emailService.get().sendInviteEmail(email, email, temporaryPassword, loginUrl);
                 log.info("Sent invite email to: {}", email);
                 return InviteResult.success();
             } catch (Exception emailEx) {

app/proprietary/src/main/java/stirling/software/proprietary/security/service/EmailService.java

@@ -115,10 +115,12 @@ public class EmailService {
      * @param to The recipient email address
      * @param username The username for the new account
      * @param temporaryPassword The temporary password
+     * @param loginUrl The URL to the login page
      * @throws MessagingException If there is an issue with creating or sending the email.
      */
     @Async
-    public void sendInviteEmail(String to, String username, String temporaryPassword)
+    public void sendInviteEmail(
+            String to, String username, String temporaryPassword, String loginUrl)
             throws MessagingException {
         String subject = "Welcome to Stirling PDF";
 
@@ -144,6 +146,14 @@ public class EmailService {
                       <div style="background-color: #fff3cd; border-left: 4px solid #ffc107; padding: 15px; margin: 20px 0; border-radius: 4px;">
                         <p style="margin: 0; color: #856404;"><strong>⚠️ Important:</strong> You will be required to change your password upon first login for security reasons.</p>
                       </div>
+                      <!-- CTA Button -->
+                      <div style="text-align: center; margin: 30px 0;">
+                        <a href="%s" style="display: inline-block; background-color: #007bff; color: #ffffff; padding: 14px 28px; text-decoration: none; border-radius: 5px; font-weight: bold;">Log In to Stirling PDF</a>
+                      </div>
+                      <p style="font-size: 14px; color: #666;">Or copy and paste this link in your browser:</p>
+                      <div style="background-color: #f8f9fa; padding: 12px; margin: 15px 0; border-radius: 4px; word-break: break-all; font-size: 13px; color: #555;">
+                        %s
+                      </div>
                       <p>Please keep these credentials secure and do not share them with anyone.</p>
                       <p style="margin-bottom: 0;">— The Stirling PDF Team</p>
                     </div>
@@ -155,7 +165,7 @@ public class EmailService {
                 </div>
                 </body></html>
                 """
-                        .formatted(username, temporaryPassword);
+                        .formatted(username, temporaryPassword, loginUrl, loginUrl);
 
         sendPlainEmail(to, subject, body, true);
     }