fathomdb 0.8.9

FathomDB facade crate — re-exports the public Rust surface of fathomdb-engine.
Documentation

FathomDB facade crate — re-exports the public Rust surface of fathomdb-engine.

The default (operator-feature-OFF) surface is the governed application surface (dev/interfaces/rust.md § Governed-surface contract): it is recovery-name-free and raw-SQL-free at the method level. The operator/recovery seam (rebuild_*, excise_source, dump_*, trace_source_ref, truncate_wal, verify_embedder, check_integrity, safe_export, recompute_mean + their report types) is gated behind the operator cargo feature, which fathomdb-cli enables. Gating, not deletion: engine behavior is identical with the feature on. See AC-074 (dev/acceptance.md) + dev/design/slice-27-fix1-operator-gate-design.md.