feat(common,core,proprietary): remove unused injections, enhance type safety, and improve test mocks (#4213)

# Description of Changes

This PR introduces several refactorings and minor enhancements across
the `common`, `core`, and `proprietary` modules:

- **Dependency Injection Cleanup**
- Removed unused constructor-injected dependencies (e.g.,
`FileOrUploadService`, `ApplicationProperties`, redundant `@Autowired`
annotations).
  - Simplified constructors to only require actively used dependencies.

- **Model Enhancements**
- Added `@NoArgsConstructor` to `FileInfo`, `PdfMetadata`, and
`SignatureFile` to improve serialization/deserialization support.

- **Service Improvements**
- Improved `JobExecutorService` content type retrieval by assigning
`MediaType` to a variable before conversion.
- Enhanced `KeyPersistenceService` with type-safe
`.filter(JwtVerificationKey.class::isInstance)`.
- Annotated `decodePublicKey` in `KeyPersistenceService` with
`@Override` for clarity.

- **Controller & API Changes**
- Updated `AdminSettingsController` to use
`TypeReference<Map<String,Object>>` for safer conversion.
- Improved long log and description strings with consistent formatting.

- **Testing Updates**
- Replaced `.lenient()` mock settings with
`.defaultAnswer(RETURNS_DEFAULTS)` for `FileToPdf` static mocks.
- Used `ArgumentMatchers.<TypeReference<List<BookmarkItem>>>any()` in
`EditTableOfContentsControllerTest` for type safety.
- Updated `UserServiceTest` default `AuthenticationType` from `SSO` to
`OAUTH2`.

- **Formatting**
  - Broke up long log/debug lines for better readability.
  - Removed redundant `@SuppressWarnings` where type safety was ensured.

These changes aim to make the codebase leaner, more type-safe, and
maintainable, while improving test reliability.

---

## Checklist

### General

- [x] I have read the [Contribution
Guidelines](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/CONTRIBUTING.md)
- [x] 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)
- [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/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.

app/core/src/main/java/stirling/software/SPDF/SPDFApplication.java

@@ -27,7 +27,6 @@ import stirling.software.SPDF.UI.WebBrowser;
 import stirling.software.common.configuration.AppConfig;
 import stirling.software.common.configuration.ConfigInitializer;
 import stirling.software.common.configuration.InstallationPathConfig;
-import stirling.software.common.model.ApplicationProperties;
 import stirling.software.common.util.UrlUtils;
 
 @Slf4j
@@ -46,17 +45,14 @@ public class SPDFApplication {
 
     private final AppConfig appConfig;
     private final Environment env;
-    private final ApplicationProperties applicationProperties;
     private final WebBrowser webBrowser;
 
     public SPDFApplication(
             AppConfig appConfig,
             Environment env,
-            ApplicationProperties applicationProperties,
             @Autowired(required = false) WebBrowser webBrowser) {
         this.appConfig = appConfig;
         this.env = env;
-        this.applicationProperties = applicationProperties;
         this.webBrowser = webBrowser;
     }
 

app/core/src/main/java/stirling/software/SPDF/config/EndpointInspector.java

@@ -6,8 +6,6 @@ import java.util.Map;
 import java.util.Set;
 import java.util.TreeSet;
 
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
 import org.springframework.context.ApplicationContext;
 import org.springframework.context.ApplicationListener;
 import org.springframework.context.event.ContextRefreshedEvent;
@@ -18,11 +16,12 @@ import org.springframework.web.servlet.mvc.method.RequestMappingInfo;
 import org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping;
 
 import lombok.RequiredArgsConstructor;
+import lombok.extern.slf4j.Slf4j;
 
 @Component
 @RequiredArgsConstructor
+@Slf4j
 public class EndpointInspector implements ApplicationListener<ContextRefreshedEvent> {
-    private static final Logger logger = LoggerFactory.getLogger(EndpointInspector.class);
 
     private final ApplicationContext applicationContext;
     private final Set<String> validGetEndpoints = new HashSet<>();
@@ -71,13 +70,13 @@ public class EndpointInspector implements ApplicationListener<ContextRefreshedEv
             }
 
             if (validGetEndpoints.isEmpty()) {
-                logger.warn("No endpoints discovered. Adding common endpoints as fallback.");
+                log.warn("No endpoints discovered. Adding common endpoints as fallback.");
                 validGetEndpoints.add("/");
                 validGetEndpoints.add("/api/**");
                 validGetEndpoints.add("/**");
             }
         } catch (Exception e) {
-            logger.error("Error discovering endpoints", e);
+            log.error("Error discovering endpoints", e);
         }
     }
 
@@ -203,10 +202,10 @@ public class EndpointInspector implements ApplicationListener<ContextRefreshedEv
     private void logAllEndpoints() {
         Set<String> sortedEndpoints = new TreeSet<>(validGetEndpoints);
 
-        logger.info("=== BEGIN: All discovered GET endpoints ===");
+        log.info("=== BEGIN: All discovered GET endpoints ===");
         for (String endpoint : sortedEndpoints) {
-            logger.info("Endpoint: {}", endpoint);
+            log.info("Endpoint: {}", endpoint);
         }
-        logger.info("=== END: All discovered GET endpoints ===");
+        log.info("=== END: All discovered GET endpoints ===");
     }
 }

app/core/src/main/java/stirling/software/SPDF/model/SignatureFile.java

@@ -2,8 +2,10 @@ package stirling.software.SPDF.model;
 
 import lombok.AllArgsConstructor;
 import lombok.Data;
+import lombok.NoArgsConstructor;
 
 @Data
+@NoArgsConstructor
 @AllArgsConstructor
 public class SignatureFile {
     private String fileName;

app/core/src/main/java/stirling/software/SPDF/service/MetricsAggregatorService.java

@@ -4,8 +4,6 @@ import java.util.HashMap;
 import java.util.Map;
 import java.util.concurrent.ConcurrentHashMap;
 
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
 import org.springframework.scheduling.annotation.Scheduled;
 import org.springframework.stereotype.Service;
 
@@ -13,15 +11,15 @@ import io.micrometer.core.instrument.MeterRegistry;
 import io.micrometer.core.instrument.search.Search;
 
 import lombok.RequiredArgsConstructor;
+import lombok.extern.slf4j.Slf4j;
 
 import stirling.software.SPDF.config.EndpointInspector;
 import stirling.software.common.service.PostHogService;
 
 @Service
 @RequiredArgsConstructor
+@Slf4j
 public class MetricsAggregatorService {
-    private static final Logger logger = LoggerFactory.getLogger(MetricsAggregatorService.class);
-
     private final MeterRegistry meterRegistry;
     private final PostHogService postHogService;
     private final EndpointInspector endpointInspector;
@@ -66,7 +64,7 @@ public class MetricsAggregatorService {
                             if ("GET".equals(method)
                                     && validateGetEndpoints
                                     && !endpointInspector.isValidGetEndpoint(uri)) {
-                                logger.debug("Skipping invalid GET endpoint: {}", uri);
+                                log.debug("Skipping invalid GET endpoint: {}", uri);
                                 return;
                             }
 
@@ -77,7 +75,7 @@ public class MetricsAggregatorService {
                             double lastCount = lastSentMetrics.getOrDefault(key, 0.0);
                             double difference = currentCount - lastCount;
                             if (difference > 0) {
-                                logger.debug("{}, {}", key, difference);
+                                log.debug("{}, {}", key, difference);
                                 metrics.put(key, difference);
                                 lastSentMetrics.put(key, currentCount);
                             }