pg_sift 1.1.0: filter pushdown, facets, parallel scans and partitioned ranking. Upgrade from 1.0: install the new files and run `ALTER EXTENSION pg_sift UPDATE`.

## Highlights

- **Filter pushdown:** a ranked scan takes a bitmap of the other quals (btree, BRIN, GIN) as a child and scores only the matches it keeps, so a selective filter stays fast with a very common term; `sift.filter_pushdown = off | on | force`, default `on`.
- **Keyword facets:** `analyzer = keyword` plus `sift.facets(index, facet_index, query, lim, nulls)` counts the matches of a query per value, from bitmaps.
- **Parallel scan:** parallel-aware `SiftScan` and `SiftCount` behind `sift.parallel_scan` (default off).
- **Partitioned tables:** `ORDER BY sift.score(ctid) DESC LIMIT k` works through a partitioned parent (per-partition ranked scans under a MergeAppend; per-partition BM25 statistics).
- **Fix:** a crash rechecking a phrase with `count(*)` or a ranked scan on an expression index, and a planner crash on an empty analyzed partition (both also affect 1.0.0).

## Compatibility and packages

- PostgreSQL 18.
- x86-64 packages for PostgreSQL 18 are attached below (`SHA256SUMS` included): `.deb` for Debian 13 and Ubuntu 24.04 (PGDG `postgresql-18`), `.rpm` for RHEL, Rocky and Alma 9 and 10 (PGDG `postgresql18-server`); other setups build from source with `make USE_PGXS=1`.

Every change: [CHANGELOG.md](https://github.com/brauliobo/pg_sift/blob/v1.1.0/CHANGELOG.md).