fix(deps): make OCI dependencies optional on release 0.5

[skamenan7]

Summary

• remove OCI-related packages from default package dependencies on release-0.5.x
• expose them through the explicit oci extra instead
• add tests that guard default/starter installs while preserving explicit OCI provider deps

Before / after proof

Built wheel metadata from v0.5.2 before the fix advertised OCI dependencies unconditionally:

Requires-Dist: oracledb>=3.4.1
Requires-Dist: oci>=2.165.0
Requires-Dist: numpy>=2.3.2

Built wheel metadata after this fix advertises them only behind the oci extra:

Provides-Extra: oci
Requires-Dist: numpy>=2.3.2; extra == "oci"
Requires-Dist: oci>=2.165.0; extra == "oci"
Requires-Dist: oracledb>=3.4.1; extra == "oci"

Test plan

• uv run --locked pytest tests/unit/distribution/test_stack_list_deps.py -q
• env UV_CACHE_DIR=/tmp/uv-cache-ogx-oci-05 UV_PYTHON_INSTALL_DIR=/tmp/uv-python-ogx-oci-05 uv build --wheel

[mergify]

This pull request has merge conflicts that must be resolved before it can be merged. @skamenan7 please rebase it. https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/working-with-forks/syncing-a-fork