Define Core

<companion_skills> These carry guidance this workflow depends on. None of them arrives on its own — load the ones a given run needs with the Skill tool, in the prepare phase, before the step that uses them. Question design and requirement formatting; load it whenever this workflow runs Load before any memory or symbol operation Load when a claim needs verification against an external source Load when a library's current API or version behavior is in question Load when the shared escalation, decision-criteria, or enforcement structures are needed </companion_skills>