Fix: use base repo only for driver solve (avoids ox overlay conflicts)
Pass opam_repositories through to build_tools_and_run so the driver
can solve against only the first (base) repo, avoiding ox-specific
packages like ocaml-compiler-libs.v0.17.0+ox that are incompatible
with the driver compiler (5.4.1).
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>