Coding-agent bypass: decision-first diagnostic - All Runs

For each of two categories, compares the natural single-shot fixture request against an otherwise-identical version where an explicit yes/no decision is forced in a separate turn before any fixture content is requested. Distinguishes "the safety check exists but doesn't gate generation in this structure" (fixable with interaction design) from "the safety check isn't being applied to this content at all" (needs training investment) — see the header comment for how to read the comparison, including a documented case where the intervention backfires.