Improve Codebase Architecture

Surface architectural friction and propose deepening opportunities — refactors that turn shallow modules into deep ones. The aim is testability and AI-navigability.

Role-gated action

This skill produces a candidate list and an agreed design, not edits. Both roles run it the same way; the difference is what happens after DESIGN AGREED:

• Write-capable role (engineer): hand the agreed design to refactoring-code to apply.
• Read-only role (reviewer): stop at DESIGN AGREED — it is the deliverable. Apply nothing.

Language detection and references

Detect the language from the file extensions in scope and load the matching reference for language-specific deepening patterns:

• Go → references/go.md
• Python → references/python.md
• TypeScript → references/typescript.md
• Web → references/web.md