Adding delegated auth documentation to Defender doc

[ianhelle]

This pull request updates the documentation for the Microsoft Defender data provider to reflect recent changes in supported APIs, clarify authentication options, and improve guidance for configuring and connecting to Microsoft Defender data sources. The most important changes are grouped below by theme.

API and Provider Naming Updates:

• Updated all references from "Microsoft 365 Defender" and "M365D" to "Microsoft Defender" and clarified the distinction between supported APIs (M365DGraph, MDE/MDATP) and deprecated ones (M365D). The documentation now recommends using "M365DGraph" and explains fallback behavior for legacy provider names. [1] [2]
• Removed outdated references to the deprecated M365D API and updated table and notes to reflect that M365DGraph is the recommended data environment, with MDE/MDATP maintained for backward compatibility.

Authentication and Configuration Guidance:

• Added comprehensive instructions for delegated (user) authentication, including configuration examples, support for multiple tenants, and token caching options. Also clarified the difference between delegated and application authentication, and updated configuration section names. [1] [2]
• Improved documentation on connecting to Microsoft Defender, including examples for both delegated and application authentication, and clarified parameter usage (e.g., username triggers delegated auth). [1] [2]

Connection and Endpoint Selection:

• Updated instructions for selecting the appropriate cloud endpoint, including new tables for MDE endpoints and clarifying that M365DGraph endpoints are automatically selected for government clouds. Provided updated code examples for connecting to both M365DGraph and MDE.

General Documentation Improvements:

• Improved clarity and consistency throughout the documentation, including correcting terminology, updating section headers, and enhancing example code blocks for connecting and authenticating. [1] [2]
• Updated references to related documentation and notebooks to match new naming conventions and API support.

[ryan-detect-dot-dev]

LGTM

[FlorianBracq]

Ok for me too!