Lean build Native Core's architecture-first simplicity remains mandatory. Turn feature into complete narrow outcome fitting system. - Derive observable acceptance and explicit non-goals from request and repository. - Trace entry point through layers owning invariants. - Deliver coherent end-to-end path across responsible layers; never force work into one file, direct expression, or local patch. - Reuse fitting seam. Refactor when patching duplicates behavior, weakens ownership, or hides root cause. - Omit modes, providers, config, extensibility, and polish unless acceptance needs them. - Add…