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/config/OpenApiConfig.java

@@ -9,16 +9,20 @@ import io.swagger.v3.oas.models.info.Info;
 import io.swagger.v3.oas.models.security.SecurityRequirement;
 import io.swagger.v3.oas.models.security.SecurityScheme;
 
+import lombok.RequiredArgsConstructor;
+
 import stirling.software.SPDF.model.ApplicationProperties;
 
 @Configuration
+@RequiredArgsConstructor
 public class OpenApiConfig {
 
     private final ApplicationProperties applicationProperties;
 
-    public OpenApiConfig(ApplicationProperties applicationProperties) {
-        this.applicationProperties = applicationProperties;
-    }
+    private static final String DEFAULT_TITLE = "Stirling PDF API";
+    private static final String DEFAULT_DESCRIPTION =
+            "API documentation for all Server-Side processing.\n"
+                    + "Please note some functionality might be UI only and missing from here.";
 
     @Bean
     public OpenAPI customOpenAPI() {
@@ -27,29 +31,27 @@ public class OpenApiConfig {
             // default version if all else fails
             version = "1.0.0";
         }
-        SecurityScheme apiKeyScheme =
-                new SecurityScheme()
-                        .type(SecurityScheme.Type.APIKEY)
-                        .in(SecurityScheme.In.HEADER)
-                        .name("X-API-KEY");
         if (!applicationProperties.getSecurity().getEnableLogin()) {
             return new OpenAPI()
                     .components(new Components())
                     .info(
                             new Info()
-                                    .title("Stirling PDF API")
+                                    .title(DEFAULT_TITLE)
                                     .version(version)
-                                    .description(
-                                            "API documentation for all Server-Side processing.\nPlease note some functionality might be UI only and missing from here."));
+                                    .description(DEFAULT_DESCRIPTION));
         } else {
+            SecurityScheme apiKeyScheme =
+                    new SecurityScheme()
+                            .type(SecurityScheme.Type.APIKEY)
+                            .in(SecurityScheme.In.HEADER)
+                            .name("X-API-KEY");
             return new OpenAPI()
                     .components(new Components().addSecuritySchemes("apiKey", apiKeyScheme))
                     .info(
                             new Info()
-                                    .title("Stirling PDF API")
+                                    .title(DEFAULT_TITLE)
                                     .version(version)
-                                    .description(
-                                            "API documentation for all Server-Side processing.\nPlease note some functionality might be UI only and missing from here."))
+                                    .description(DEFAULT_DESCRIPTION))
                     .addSecurityItem(new SecurityRequirement().addList("apiKey"));
         }
     }