-- pg_turbovec v1.15.0 -- Phase C follow-up: operator-path allowlist.
--
-- This file is a *reference mirror*. The authoritative install
-- script is generated by `cargo pgrx schema`.
--
-- v1.15.0 brings the in-kernel allowlist pushdown -- previously only
-- available via the flat turbovec.knn(..., allowed) FUNCTION -- to the
-- normal index-AM ORDER BY emb <=> q LIMIT k operator path, on BOTH
-- flat AND IVF indexes (and the out-of-core cell-scoped path):
--
--   1. New session GUC turbovec.allowlist (string, default ''): a CSV
--      of heap TIDs (encoded as bigint). When set, the scan ANDs the
--      allowed slots into the slot mask it hands the SIMD kernel, so
--      the kernel short-circuits 32-vector blocks with no allowed
--      slot before any LUT work (the same block-skip knn() gets). On
--      an IVF index the allowlist is ANDed with the probed-cell mask,
--      scoping the skip to probed cells AND allowed slots. Empty/unset
--      GUC is the exact prior behaviour with zero added cost. Set it
--      with SET / set_config() around the query; RESET to clear.
--
--   2. New function turbovec.tid_to_bigint(tid) -> bigint: the
--      ergonomic encoder for building the allowlist from ctid
--      (returns the (block << 32) | offset value the AM stores per
--      slot). cargo pgrx schema emits its CREATE FUNCTION into the
--      authoritative 1.14.0--1.15.0 upgrade script; this reference
--      mirror does not duplicate it.
--
-- NOTE: the allowlist is a set of heap TIDs, not an id-column -- the
-- index AM keys vectors by heap TID, not by any heap id column.
-- turbovec.knn(..., allowed) remains the id-column path. This is a
-- pre-materialized id-set channel, NOT arbitrary-WHERE pushdown. See
-- docs/FILTERING.md sections 3.5, 6, and 7.
--
-- The on-disk relfile format is UNCHANGED (MetaPageData::version = 4);
-- the new GUC + function are purely additive, and there is no
-- index-AM scan-key reinterpretation (the dangerous amrescan rewrite
-- is avoided). There is no on-disk migration. `ALTER EXTENSION
-- pg_turbovec UPDATE TO '1.15.0';` resolves cleanly. No REINDEX is
-- needed -- existing indexes work unchanged.