chore(beaking-changes): refactor and simplify codebase

[shivarm]

This pull request includes several changes to the MongoDB Atlas SDK documentation and codebase, focusing on improvements to backup functionality, renaming methods for consistency, and enhancing the project's documentation. The most important changes are summarized below:

Documentation Improvements:

• Added dark/light theme support by including the docsify-darklight-theme plugin

Method Renaming:

• Renamed auditLoggingPlugin to auditLog for consistency. Updated corresponding imports
• Renamed queryCachingPlugin to queryCache for consistency. Updated corresponding imports

Backup Functionality:

• src/core/dataBackup.ts: Enhanced the backupModel method to support optional fields, allowing selective data backup.
• examples/typescript/src/controllers/backupController.ts: Added a new controller for handling user backups using the enhanced backupModel method.