Enhance Java Development Configuration and Code Formatting (#2991)

# Description of Changes

Please provide a summary of the changes, including:

This PR improves Java development settings and code formatting by:
- Removing the deprecated `Checkstyle` extension from
`.vscode/extensions.json`.
- Updating `.vscode/settings.json` with:
  - Structured formatting for better readability.
  - Improved Java formatting with `google-java-format`.
  - Enhanced auto-save behavior.
  - Additional Java cleanup actions for better code quality.
  - Optimized project resource filtering.
  - More precise import sorting and ordering.
- Refining `build.gradle` to:
- Extend the `importOrder` rule to include `jakarta`, `lombok`, `me`,
and `stirling`.
  - Improve `spotless` formatting configurations.

These changes streamline the development workflow, enhance code
consistency, and improve maintainability.

---

## 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/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
(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/DeveloperGuide.md#6-testing)
for more details.

.vscode/extensions.json

@@ -9,7 +9,6 @@
     // "ms-vscode-remote.vscode-remote-extensionpack", // Remote Development Pack for SSH, WSL, and Containers
     "Oracle.oracle-java", // Oracle Java extension with additional features for Java development
     "redhat.java", // Java support by Red Hat with IntelliSense, debugging, and code navigation
-    "shengchen.vscode-checkstyle", // Checkstyle integration for Java code quality checks
     "streetsidesoftware.code-spell-checker", // Spell checker for code to avoid typos
     "vmware.vscode-boot-dev-pack", // Developer tools for Spring Boot by VMware
     "vmware.vscode-spring-boot", // Spring Boot tools by VMware for enhanced Spring development