Update: Microservices Security

This issue is created based on the foundational work contributed by @dadrus in the following PRs: #1746, #1808, #1809. The proposal is to restructure and improve the existing Microservice Security CS. One proposed approach is to align the updated CS with the core concepts outlined in @dadrus blog post Core Concepts. This also involves migrating cheat sheets introduced in mentioned PRs to the appropriate directories and establishing cross-references.

Additional considerations:

1. The content of updated CS should be tailored for software developers ("builders") and provides actionable insights for the following tasks:

   • help developers quickly identify security design patterns to be implemented based on their specific tech stack, threat model, non-functional requirements, etc;
   • facilitate source code and architectural reviews to ensure alignment with microservice security best practices.

2. LLM optimization: Ensure the updated CS is effective when used as context for LLMs, e.g., avoid overly complex formatting and minimize reliance on images to ensure the core logic is fully captured in the text. This will allow end-users to include the CS in LLM prompts to receive AI-driven design feedback or code analysis.