test: include pyproject in Bazel pytest data

[haasonsaas]

Summary

• include pyproject.toml in the Bazel pytest runfiles so the pytest config used by tests/pytest_main.py is present under Bazel
• closes the review-feedback guardrail gap from [codex] Guardrail backlog: Test coverage gap (test-coverage-gap) .github#85 / ci: add Bazel RBE lane #19

Verification

• git diff --check
• python3 - <<PY ... confirmed BUILD.bazel includes pyproject.toml

Note

• bazelisk is not installed locally in this Codex environment, so CI is the Bazel verification authority for this PR.

[cursor]

PR Summary

Low Risk
Low risk: a Bazel metadata-only change that only affects what files are available to tests at runtime.

Overview
Ensures Bazel test runfiles include pyproject.toml by adding it to SERVICE_DATA in BUILD.bazel, so Bazel-invoked pytest runs can pick up the same pytest configuration as non-Bazel runs.

^{Reviewed by Cursor Bugbot for commit 9cb20ed. Bugbot is set up for automated code reviews on this repo. Configure here.}