improve-codebase-architecturelisted

# 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. This command is _informed_ by the project's domain model and built on a shared design vocabulary: - Invoke the `codebase-design` skill for the architecture vocabulary (**module**, **interface**, **depth**, **seam**, **adapter**, **leverage**, **locality**) and its principles (the deletion test, "the interface is the test surface", "one adapter = hypothetical seam, two = real"). Use these terms exactly in every suggestion, and don't drift into "component," "service," "API," or "boundary." - The project's domain glossary and naming conventions give names to good seams; its ADRs record decisions this command should not re-litigate. The project map in `AGENTS.md` says where each lives; skip whichever the project does not keep. ## Process ### 1. Explore **Scope before you scan: YAGNI.** Deepening a module pays off by making future changes to it easier, so put extra weight on the parts of the codebase that have recently changed. Decide *where* to look before you look: - If the user named a direction (a module, a subsystem, a pain point), take it, and skip the inference below. - Otherwise, walk back a good stretch of the commit history (`git log --oneline`) to find the codebase's hot spots, the files and areas that keep coming up, and let those paths pull your attention first. If