vmm-tests: restore incubator profile staging

[John Starks (jstarks)]

Stage incubator profiles based on whether the run uses an incubator rather than whether the content initializer still owns the incubator binary artifact. This fixes direct vmm-tests-run invocations whose default profile is resolved beneath the test content directory. Also preserve the failing profile path in read errors by using fs-err.

[Copilot]

🟢 Approval recommended

The changes are small, compile-time enforced via request struct plumbing, and directly align with the stated fix for incubator profile staging and error reporting.

Pull request overview

This PR fixes vmm-tests incubator profile staging by copying incubator profile TOMLs into the test content directory based on whether an incubator run is requested (via profile usage), rather than whether the content initializer happens to own the incubator binary artifact. It also improves read error reporting for incubator profiles by switching to fs-err.

Changes:

• Use fs_err::read_to_string when loading incubator profiles to preserve path information in I/O errors.
• Add a needs_incubator_profiles flag to vmm-tests content-dir initialization and use it to control copying petri/incubator/profiles/*.toml.
• Plumb needs_incubator_profiles through the local-build and archive-consume nextest vmm-tests jobs.

File summaries

File	Description
petri/incubator/src/profile.rs	Switches profile file loading to fs-err for better error detail (path-preserving I/O errors).
petri/incubator/Cargo.toml	Adds fs-err dependency for the incubator crate.
flowey/flowey_lib_hvlite/src/init_vmm_tests_content_dir.rs	Introduces and uses needs_incubator_profiles to stage incubator profile TOMLs into the test content dir.
flowey/flowey_lib_hvlite/src/_jobs/local_build_and_run_nextest_vmm_tests.rs	Sets needs_incubator_profiles based on whether an incubator profile is configured for the run.
flowey/flowey_lib_hvlite/src/_jobs/consume_and_test_nextest_vmm_tests_archive.rs	Propagates needs_incubator_profiles for archive-based runs when incubator execution is enabled.
Cargo.lock	Records the incubator crate’s new dependency on fs-err.

Review details

• Files reviewed: 5/6 changed files
• Comments generated: 0
• Review effort level: Lite

---

💡 Add a code-review agent skill or configure MCP servers for context-aware, tailored reviews. Learn more in the docs.