Docs Uth — Documentation skill for Claude Code

Add a new page to the "Under the Hood" Documentation

Explain the provided feature in the docs: add a new page to @docs/under-the-hood/

Don't present the changes as "changes". Describe as if it were always like this. We are documenting the (new) current solution as the new normal.

---

Use our under-the-hood template:

Structure: Principle → Usage variants → Interfaces → Architecture (Mermaid) → Implementation → Reference tables

Approach:

• Why before how

• Exhaustive case tables (Scenario