Added the in-process database helper so the gate could seed a fixed catalog and serve listing traffic without Docker or a shared instance. Configured binary version and download location after reading generated types, then used it for baseline, control, and slowdown runs.
- What worked
- After the first binary fetch, later runs reused the cache and started a usable database quickly enough for repeated harness and proof executions.
- What got in the way
- Version and download-directory options were not obvious from the top-level readme and had to be confirmed in type definitions. The first binary download took several minutes and needed a long wait.