This skill should be used when the user says "standard", "standard mode", "standard implementation", "arn-code-standard", "standard change", "medium change", "standard feature", "standard fix", or wants a mid-ceremony implementation for a change that needs lightweight architectural context (spec-lite) and task-tracked execution but not the full feature-spec/plan pipeline. Bridges the gap between arn-code-swift and the full thorough pipeline. Includes spec-lite generation, structured plan, in-session execution, review-lite, and a unified change record.