-- pg_tre 1.5.8 -> 1.6.0 upgrade.
--
-- 1.6.0 has no SQL-catalog changes, but it is a BREAKING on-disk
-- change: the vendored sparsemap was updated to 4.0.0, whose
-- serialized format widened per-chunk start offsets from 32 to 64
-- bits.  That fixes silent DATA LOSS for sparsemap indices >= 2^32 --
-- which pg_tre reaches on any heap larger than ~512 MB (TIDs are
-- packed as (block << 16) | offset).
--
-- The new sparsemap wire format is NOT backward-readable, so indexes
-- built by pg_tre < 1.6 cannot be read in place.  After installing the
-- new shared library and running this update, you MUST rebuild every
-- pg_tre index:
--
--     REINDEX INDEX  your_tre_index;        -- per index, or
--     REINDEX TABLE  your_table;            -- all indexes on a table
--
-- pg_tre_read() rejects pre-v6 pages with a clear error + REINDEX hint
-- rather than returning wrong rows, so an un-rebuilt index fails loudly
-- on first scan instead of silently.
--
-- REINDEX is also the remedy for any data already lost to the
-- 32-bit-offset bug on large heaps under pg_tre < 1.6.
--
-- Intentionally empty (no catalog DDL).