formattingand autowired constructors (#2557)

# Description
This pull request includes several changes aimed at improving the code
structure and removing redundant code. The most significant changes
involve reordering methods, removing unnecessary annotations, and
refactoring constructors to use dependency injection.
Autowired now comes via constructor (which also doesn't need autowired
annotation as its done by default for configuration)



## Checklist

- [ ] I have read the [Contribution
Guidelines](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/CONTRIBUTING.md)
- [ ] I have performed a self-review of my own code
- [ ] I have attached images of the change if it is UI based
- [ ] I have commented my code, particularly in hard-to-understand areas
- [ ] If my code has heavily changed functionality I have updated
relevant docs on [Stirling-PDFs doc
repo](https://github.com/Stirling-Tools/Stirling-Tools.github.io/blob/main/docs/)
- [ ] My changes generate no new warnings
- [ ] I have read the section [Add New Translation
Tags](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/HowToAddNewLanguage.md#add-new-translation-tags)
(for new translation tags only)

src/main/java/org/apache/pdfbox/examples/signature/CreateSignatureBase.java

@@ -97,14 +97,14 @@ public abstract class CreateSignatureBase implements SignatureInterface {
         this.privateKey = privateKey;
     }
 
-    public final void setCertificateChain(final Certificate[] certificateChain) {
-        this.certificateChain = certificateChain;
-    }
-
     public Certificate[] getCertificateChain() {
         return certificateChain;
     }
 
+    public final void setCertificateChain(final Certificate[] certificateChain) {
+        this.certificateChain = certificateChain;
+    }
+
     public void setTsaUrl(String tsaUrl) {
         this.tsaUrl = tsaUrl;
     }
@@ -152,6 +152,10 @@ public abstract class CreateSignatureBase implements SignatureInterface {
         }
     }
 
+    public boolean isExternalSigning() {
+        return externalSigning;
+    }
+
     /**
      * Set if external signing scenario should be used. If {@code false}, SignatureInterface would
      * be used for signing.
@@ -163,8 +167,4 @@ public abstract class CreateSignatureBase implements SignatureInterface {
     public void setExternalSigning(boolean externalSigning) {
         this.externalSigning = externalSigning;
     }
-
-    public boolean isExternalSigning() {
-        return externalSigning;
-    }
 }

src/main/java/org/apache/pdfbox/examples/signature/TSAClient.java

@@ -51,15 +51,13 @@ public class TSAClient {
 
     private static final DigestAlgorithmIdentifierFinder ALGORITHM_OID_FINDER =
             new DefaultDigestAlgorithmIdentifierFinder();
-
+    // SecureRandom.getInstanceStrong() would be better, but sometimes blocks on Linux
+    private static final Random RANDOM = new SecureRandom();
     private final URL url;
     private final String username;
     private final String password;
     private final MessageDigest digest;
 
-    // SecureRandom.getInstanceStrong() would be better, but sometimes blocks on Linux
-    private static final Random RANDOM = new SecureRandom();
-
     /**
      * @param url the URL of the TSA service
      * @param username user name of TSA