Fall back to project root when file resolver cannot find file

[holyfuchs]

The fileResolver always resolved file paths relative to the test file that triggered the import. This breaks when a helper script is shared across test files in different directories.

For example, given this layout:

tests/some_test.cdc -> imports "test_helpers" -> reads some_contract.cdc -> resolves to tests/some_contract.cdc
tests/mocks/some_test.cdc -> imports "../test_helpers" -> reads some_contract.cdc -> resolves to tests/mocks/some_contract.cdc

This essentially forces having all test files in a single directory.

The fix adds a fallback: if a file isn't found at the path relative to the test file, it retries the path relative to the project root (the working directory where flow.json lives).
The original error is returned only if both lookups fail, so existing behavior is fully preserved.
Any test that already works continues to work unchanged.

[github-actions]

Dependency Review

✅ No vulnerabilities or license issues or OpenSSF Scorecard issues found.

Snapshot Warnings

⚠️: No snapshots were found for the head SHA df4a9d8.

Ensure that dependencies are being submitted on PR branches and consider enabling retry-on-snapshot-warnings. See the documentation for more information and troubleshooting advice.

Scanned Files

None

[codecov-commenter]

Codecov Report

❌ Patch coverage is 80.00000% with 1 line in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
internal/test/test.go	80.00%	0 Missing and 1 partial ⚠️

📢 Thoughts on this report? Let us know!

[janezpodhostnik]

can you move this to the top of the function?

[holyfuchs]

Not sure but all of the tests have same setup, I just copied it, would rather leave this consistent.