chore(build): centralize Gradle dependency version management

[Ludy87]

Description of Changes

This change centralizes several dependency version declarations into shared Gradle version properties and updates module build files to reference those properties instead of hardcoded version strings.

What was changed

• Added centralized version properties in the root build.gradle for:
  • commons-io
  • commons-lang3
  • rhino
  • okhttp BOM
  • gson
  • guava
  • bucket4j
  • archunit
• Replaced hardcoded dependency versions across multiple modules with shared variables.
• Updated resolutionStrategy.force declarations to use centralized version properties.
• Updated dependency constraints and BOM references to use shared version variables.
• Removed duplicate version declarations and improved consistency across modules.

Why the change was made

• Reduce duplication of dependency version definitions.
• Simplify future dependency upgrades and maintenance.
• Ensure consistent dependency versions across all modules.
• Improve readability and reduce the risk of version drift between subprojects.

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Checklist

General

• I have read the Contribution Guidelines
• I have read the Stirling-PDF Developer Guide (if applicable)
• I have read the How to add new languages to Stirling-PDF (if applicable)
• I have performed a self-review of my own code
• My changes generate no new warnings

Documentation

• I have updated relevant docs on Stirling-PDF's doc repo (if functionality has heavily changed)
• I have read the section Add New Translation Tags (for new translation tags only)

Translations (if applicable)

• I ran scripts/counter_translation.py

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 run task check to verify linters, typechecks, and tests pass
• I have tested my changes locally. Refer to the Testing Guide for more details.

[stirlingbot]

✅ Backend License Check Passed

All backend dependencies have valid and allowed licenses.

The backend license report has been updated successfully.

[stirlingbot]

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