Refactor codebase to replace explicit constructors with Lombok annotations and remove boilerplat (#3415)

# Description of Changes

- **What was changed:**  
- Removed explicit constructor definitions annotated with `@Autowired`
across services, controllers, filters, and schedulers.
- Added Lombok’s `@RequiredArgsConstructor` to automatically generate
required-args constructors and eliminate boilerplate.
- Introduced other Lombok annotations (`@Data`, `@Getter`, `@Setter`,
`@EqualsAndHashCode`, `@NoArgsConstructor`) on model and API classes to
replace manual getters/setters and constructors.
- Standardized string comparisons to use the constant-first form (e.g.,
`"value".equals(variable)`).
- Cleaned up unused imports and organized OpenAPI configuration by
extracting default title/description constants.

- **Why the change was made:**  
  - To reduce repetitive boilerplate code and improve maintainability.  
- To leverage Lombok for cleaner, more consistent dependency injection
and data modeling.
  - To ensure a uniform coding style across the entire codebase.

#3406

---

## Checklist

### General

- [x] 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/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/HowToAddNewLanguage.md)
(if applicable)
- [x] I have performed a self-review of my own code  
- [x] 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/HowToAddNewLanguage.md#add-new-translation-tags)
(for new translation tags only)

### UI Changes (if applicable)

- [ ] Screenshots or videos demonstrating the UI changes are attached  

### Testing (if applicable)

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

src/main/java/stirling/software/SPDF/model/api/GeneralFile.java

@@ -6,11 +6,9 @@ import io.swagger.v3.oas.annotations.media.Schema;
 
 import lombok.Data;
 import lombok.EqualsAndHashCode;
-import lombok.NoArgsConstructor;
 
 @Data
 @EqualsAndHashCode
-@NoArgsConstructor
 public class GeneralFile {
 
     @Schema(description = "The input file")

src/main/java/stirling/software/SPDF/model/api/HandleDataRequest.java

@@ -6,10 +6,8 @@ import io.swagger.v3.oas.annotations.media.Schema;
 
 import lombok.Data;
 import lombok.EqualsAndHashCode;
-import lombok.NoArgsConstructor;
 
 @Data
-@NoArgsConstructor
 @EqualsAndHashCode
 public class HandleDataRequest {
 

src/main/java/stirling/software/SPDF/model/api/ImageFile.java

@@ -6,10 +6,8 @@ import io.swagger.v3.oas.annotations.media.Schema;
 
 import lombok.Data;
 import lombok.EqualsAndHashCode;
-import lombok.NoArgsConstructor;
 
 @Data
-@NoArgsConstructor
 @EqualsAndHashCode
 public class ImageFile {
     @Schema(description = "The input image file")

src/main/java/stirling/software/SPDF/model/api/MultiplePDFFiles.java

@@ -6,10 +6,8 @@ import io.swagger.v3.oas.annotations.media.Schema;
 
 import lombok.Data;
 import lombok.EqualsAndHashCode;
-import lombok.NoArgsConstructor;
 
 @Data
-@NoArgsConstructor
 @EqualsAndHashCode
 public class MultiplePDFFiles {
     @Schema(description = "The input PDF files", type = "array", format = "binary")

src/main/java/stirling/software/SPDF/model/api/PDFComparison.java

@@ -4,10 +4,8 @@ import io.swagger.v3.oas.annotations.media.Schema;
 
 import lombok.Data;
 import lombok.EqualsAndHashCode;
-import lombok.NoArgsConstructor;
 
 @Data
-@NoArgsConstructor
 @EqualsAndHashCode(callSuper = true)
 public class PDFComparison extends PDFFile {
 

src/main/java/stirling/software/SPDF/model/api/PDFComparisonAndCount.java

@@ -4,10 +4,8 @@ import io.swagger.v3.oas.annotations.media.Schema;
 
 import lombok.Data;
 import lombok.EqualsAndHashCode;
-import lombok.NoArgsConstructor;
 
 @Data
-@NoArgsConstructor
 @EqualsAndHashCode(callSuper = true)
 public class PDFComparisonAndCount extends PDFComparison {
     @Schema(description = "Count")

src/main/java/stirling/software/SPDF/model/api/PDFWithPageNums.java

@@ -10,14 +10,10 @@ import io.swagger.v3.oas.annotations.media.Schema.RequiredMode;
 
 import lombok.Data;
 import lombok.EqualsAndHashCode;
-import lombok.NoArgsConstructor;
-import lombok.extern.slf4j.Slf4j;
 
 import stirling.software.SPDF.utils.GeneralUtils;
 
 @Data
-@NoArgsConstructor
-@Slf4j
 @EqualsAndHashCode(callSuper = true)
 public class PDFWithPageNums extends PDFFile {
 
@@ -32,8 +28,7 @@ public class PDFWithPageNums extends PDFFile {
 
     @Hidden
     public List<Integer> getPageNumbersList(PDDocument doc, boolean oneBased) {
-        int pageCount = 0;
-        pageCount = doc.getNumberOfPages();
+        int pageCount = doc.getNumberOfPages();
         return GeneralUtils.parsePageList(pageNumbers, pageCount, oneBased);
     }
 }

src/main/java/stirling/software/SPDF/model/api/SplitPdfByChaptersRequest.java

@@ -4,10 +4,8 @@ import io.swagger.v3.oas.annotations.media.Schema;
 
 import lombok.Data;
 import lombok.EqualsAndHashCode;
-import lombok.NoArgsConstructor;
 
 @Data
-@NoArgsConstructor
 @EqualsAndHashCode(callSuper = false)
 public class SplitPdfByChaptersRequest extends PDFFile {
     @Schema(description = "Whether to include Metadata or not", example = "true")

src/main/java/stirling/software/SPDF/model/api/SplitPdfBySectionsRequest.java

@@ -4,10 +4,8 @@ import io.swagger.v3.oas.annotations.media.Schema;
 
 import lombok.Data;
 import lombok.EqualsAndHashCode;
-import lombok.NoArgsConstructor;
 
 @Data
-@NoArgsConstructor
 @EqualsAndHashCode(callSuper = true)
 public class SplitPdfBySectionsRequest extends PDFFile {
     @Schema(description = "Number of horizontal divisions for each PDF page", example = "2")

src/main/java/stirling/software/SPDF/model/api/user/UpdateUserDetails.java

@@ -4,10 +4,8 @@ import io.swagger.v3.oas.annotations.media.Schema;
 
 import lombok.Data;
 import lombok.EqualsAndHashCode;
-import lombok.NoArgsConstructor;
 
 @Data
-@NoArgsConstructor
 @EqualsAndHashCode(callSuper = true)
 public class UpdateUserDetails extends UpdateUserUsername {
 

src/main/java/stirling/software/SPDF/model/api/user/UpdateUserUsername.java

@@ -4,10 +4,8 @@ import io.swagger.v3.oas.annotations.media.Schema;
 
 import lombok.Data;
 import lombok.EqualsAndHashCode;
-import lombok.NoArgsConstructor;
 
 @Data
-@NoArgsConstructor
 @EqualsAndHashCode(callSuper = true)
 public class UpdateUserUsername extends UsernameAndPass {
 

src/main/java/stirling/software/SPDF/model/api/user/Username.java

@@ -4,11 +4,9 @@ import io.swagger.v3.oas.annotations.media.Schema;
 
 import lombok.Data;
 import lombok.EqualsAndHashCode;
-import lombok.NoArgsConstructor;
 
 @Data
 @EqualsAndHashCode
-@NoArgsConstructor
 public class Username {
 
     @Schema(description = "username of user")

src/main/java/stirling/software/SPDF/model/api/user/UsernameAndPass.java

@@ -4,10 +4,8 @@ import io.swagger.v3.oas.annotations.media.Schema;
 
 import lombok.Data;
 import lombok.EqualsAndHashCode;
-import lombok.NoArgsConstructor;
 
 @Data
-@NoArgsConstructor
 @EqualsAndHashCode(callSuper = true)
 public class UsernameAndPass extends Username {