Update LLMs PoC introduction

[javimed]

Description

Update Leveraging LLMs for alert enrichment PoC introduction.

Checks

Docs building

• [X] Compiles without warnings.

  Code formatting and web optimization

• [X] Uses three spaces indentation.
• [X] Adds or updates meta descriptions accordingly.
• [X] Updates the redirects.js script if necessary (check this guide).

  Writing style

• [ ] Uses present tense, active voice, and semi-formal registry.
• [ ] Uses short, simple sentences.
• [ ] Uses bold for user interface elements, italics for key terms or emphasis, and code font for Bash commands, file names, REST paths, and code.