Fetch fields for up to 25 locations in one request

The batch form of /v1/fetch: one field selection applied to a list of locations (each lat+lng or address). Results are index-aligned with the request and each is the same shape as a /v1/fetch response body; a location that fails resolves to an ok:false entry with the same error object the single endpoint would have returned, never failing the batch. Public Fetch is free. Send an optional Idempotency-Key header (8-128 chars of [A-Za-z0-9_-]) to make retries safe: if the response is lost in transit (a gateway 502, a client read timeout), retrying with the SAME key and body within 24h returns the already-computed result at zero additional source run, marked replayed:true (replays do count against your per-minute rate limit). Reusing a key with a different body is a 409 idempotency_key_reused; a retry racing the original computation is a 409 batch_in_progress with Retry-After. For long-running batches prefer POST /v1/runs (kind fetch_batch), which survives disconnects by design.