Identity + settlement disclosure for one pair (v2)

Thin identity + settlement view of one pair: {id, slug, title, status, settlement}.

Accepts dino_<uuid>, a bare UUID, or a persisted poly_slug. Never fetches Centrifugo history or prices — settlement is pull-only, static fine print (§4 API_SHAPE_v2.md), so this endpoint skips the price join GET /v2/pairs/{market_id} does. settlement carries only the agree/diverge verdict, never the raw per-venue Kalshi winner (M8/§9.4) — same guarantee as the parent detail endpoint, inherited from the same to_market() serializer.