Patch release over v0.7.1: write-path latency reductions (#288 direct table
opener, #298 schema-once + open-each-table-once) and three correctness fixes on
the maintenance and recovery paths (#297 optimize survives a cross-process write
race, #291 optimize compacts the internal metadata tables + non-destructive
auto_cleanup strip, #296 recovery converges under a concurrent manifest advance).
No breaking changes, no on-disk format change, no migration.
Version coherence: all 7 crate manifests + path-dep constraints, Cargo.lock,
openapi.json, and the AGENTS.md surveyed version bumped 0.7.1 -> 0.7.2. Build
green under --locked; OpenAPI drift check green.
