refactor: Enhance Docker image retrieval logic in ContainerManager

[usnavy13]

• Updated the get_image_for_language method to implement fallback logic for Docker images, allowing for a more robust image resolution process.
• Added error handling to provide clear feedback when no suitable Docker image is found.
• Improved security hardening configurations by documenting limitations and applying ulimits for process and file descriptor management.

Description

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Fixes # (issue)

Type of change

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• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update

How Has This Been Tested?

Please describe the tests that you ran to verify your changes. Provide instructions so we can reproduce. Please also list any relevant details for your test configuration

• Test A
• Test B

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules