Rule-engine-based list endpoint — an alternative to the simple filter.* query params on the plain list endpoint, for building complex AND/OR filter conditions. Get the field key enum for filter_rules from the corresponding Meta Filter endpoint. fields_to_select is restricted to a fixed allowlist of fields: estimate_uid, estimate_no, prefix, associations, reference_no, job, customer, customer_name, estimate_date, estimate_date_dt, total, tags, expiry_date, expiry_date_dt, accepted_date, sent_date, converted_date, estimate_status, deposit, is_expired, is_deleted, is_active, is_converted, custom_fields, custom_field_internal_object, total_discount, is_proposal, proposal_title, proposal_template, proposal_options, created_by, sold_by_user, created_at, updated_at, external_id, external_status, business_unit, waiting_on_po, waiting_on_po_uids, waiting_on_mr, waiting_on_mr_uids, cpq_status, pending_option_selection, payment_methods. Supports cursor pagination — pass cursor_pagination: true (or any of cursor/prev_cursor/last_page) to switch response modes.