Close a perp position (full/partial) on its venue (non-custodial).

position_id is venue-native (for Drift it is the market symbol). close_pct in (0, 100]. Returns an UNSIGNED tx / signing payload to sign + broadcast.

jurisdiction: closes are geo-gated too -- see place_perp_order.

idempotency_key (optional): a client-generated UUID. Retrying with the same key + same args replays the original result instead of re-closing the position. Reuse the SAME key across the build call and its signed_transaction completion call -- see place_perp_order; the two legs dedupe independently, so this never raises IDEMPOTENCY_CONFLICT.

signed_transaction / verify (two-phase execution): see place_perp_order -- re-call with the signed payload and Crank relays it by custody tier and verifies the result.

venue_action (optional, completion leg only): see place_perp_order -- pass back the build leg's extra['venue_action'] (e.g. Jupiter's decrease-position) so the relay route is the venue's own declared one instead of one inferred from the signed bytes.

simulate (optional): true = rehearse this call. The full gate stack (capability, kill switch, session signer, wallet policy, permission mode, soft launch, venue / compliance / token checks, fee quote) is evaluated read-only and returned as verdicts + would_execute, with a paper fill where one applies. Nothing is built, signed, broadcast or charged. Omitted = your wallet's default_simulate setting; false = execute.