Why: The runner cannot reach github.com, so cloning actions/checkout timed out before any test ran.
Evidence: The Go 1.27.1 tarball is available from mirrors.aliyun.com. Checkout uses the job token and GITHUB_SHA.
Impact: Submodule checkout still requires SUBMODULE_TOKEN. A missing secret fails the job with that message.
Refs: feature/agent-stack-r0-r1
Co-authored-by: Cursor <cursoragent@cursor.com>
Why: Checkout did not recurse, so go vet failed without deps/agent-intent, and the runner has no SSH key.
Evidence: Workflow uses recursive HTTPS checkout, setup-go 1.27, GOPROXY=https://goproxy.cn,direct, and PROJECT.md vet plus test plus race.
Impact: vet-and-test runs on ubuntu-latest. SUBMODULE_TOKEN must be set by the owner before checkout can succeed.
Refs: feature/agent-stack-r0-r1
Co-authored-by: Cursor <cursoragent@cursor.com>