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: SSH submodule checkout failed on the runner, and the docker job required a path this repo does not have.
Evidence: vet-and-test uses recursive HTTPS checkout, setup-go 1.27, GOPROXY, and GOWORK=off vet, test, and race. The docker job only checks go.mod.
Impact: 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>