Settings display demo and login fix (#4884)

# Description of Changes
<img width="1569" height="980" alt="image"
src="https://github.com/user-attachments/assets/dca1c227-ed84-4393-97a1-e3ce6eb1620b"
/>

<img width="1596" height="935" alt="image"
src="https://github.com/user-attachments/assets/2003e1be-034a-4cbb-869e-6d5d912ab61d"
/>

<img width="1543" height="997" alt="image"
src="https://github.com/user-attachments/assets/fe0c4f4b-eeee-4db4-a041-e554f350255a"
/>


---

## 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/controller/api/ProprietaryUIDataController.java

@@ -116,6 +116,10 @@ public class ProprietaryUIDataController {
         LoginData data = new LoginData();
         Map<String, String> providerList = new HashMap<>();
         Security securityProps = applicationProperties.getSecurity();
+
+        // Add enableLogin flag so frontend doesn't need to call /app-config
+        data.setEnableLogin(securityProps.getEnableLogin());
+
         OAUTH2 oauth = securityProps.getOauth2();
 
         if (oauth != null && oauth.getEnabled()) {
@@ -448,6 +452,7 @@ public class ProprietaryUIDataController {
 
     @Data
     public static class LoginData {
+        private Boolean enableLogin;
         private Map<String, String> providerList;
         private String loginMethod;
         private boolean altLogin;

app/proprietary/src/main/java/stirling/software/proprietary/security/filter/UserAuthenticationFilter.java

@@ -223,7 +223,8 @@ public class UserAuthenticationFilter extends OncePerRequestFilter {
                 || trimmedUri.startsWith("/saml2")
                 || trimmedUri.startsWith("/api/v1/auth/login")
                 || trimmedUri.startsWith("/api/v1/auth/refresh")
-                || trimmedUri.startsWith("/api/v1/auth/logout");
+                || trimmedUri.startsWith("/api/v1/auth/logout")
+                || trimmedUri.startsWith("/api/v1/proprietary/ui-data/login");
     }
 
     private enum UserLoginType {