V2 Validate PDF Signature tool (#4679)

# Description of Changes

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Please provide a summary of the changes, including:

- What was changed
- Why the change was made
- Any challenges encountered

Closes #(issue_number)
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---

## 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: Anthony Stirling <77850077+Frooodle@users.noreply.github.com>

app/common/src/main/java/stirling/software/common/model/ApplicationProperties.java

@@ -120,6 +120,7 @@ public class ApplicationProperties {
         private String loginMethod = "all";
         private String customGlobalAPIKey;
         private Jwt jwt = new Jwt();
+        private Validation validation = new Validation();
 
         public Boolean isAltLogin() {
             return saml2.getEnabled() || oauth2.getEnabled();
@@ -308,6 +309,41 @@ public class ApplicationProperties {
             private int keyRetentionDays = 7;
             private boolean secureCookie;
         }
+
+        @Data
+        public static class Validation {
+            private Trust trust = new Trust();
+            private boolean allowAIA = false;
+            private Aatl aatl = new Aatl();
+            private Eutl eutl = new Eutl();
+            private Revocation revocation = new Revocation();
+
+            @Data
+            public static class Trust {
+                private boolean serverAsAnchor = true;
+                private boolean useSystemTrust = false;
+                private boolean useMozillaBundle = false;
+                private boolean useAATL = false;
+                private boolean useEUTL = false;
+            }
+
+            @Data
+            public static class Aatl {
+                private String url = "https://trustlist.adobe.com/tl.pdf";
+            }
+
+            @Data
+            public static class Eutl {
+                private String lotlUrl = "https://ec.europa.eu/tools/lotl/eu-lotl.xml";
+                private boolean acceptTransitional = false;
+            }
+
+            @Data
+            public static class Revocation {
+                private String mode = "none";
+                private boolean hardFail = false;
+            }
+        }
     }
 
     @Data