chore: stlc plumbing smoke test from kernel/kernel PR #3095

Author: kernel-internal[bot]

.stlc-integration-test/smoke-test.md

@@ -0,0 +1,13 @@
+# stlc plumbing smoke test — SIMULATED OUTPUT
+
+Written by the `integration-test` job of `.github/workflows/stlc-generate.yml`
+in kernel/kernel. The stlc generator was not installed or run — this
+marker file is the entire diff, and it says nothing about generator
+output or parity with hosted Stainless.
+
+What it proves: the workflow can mint a GitHub App token for this repo,
+push a branch to it, open/update a draft PR, and clean up afterwards.
+
+Source: kernel/kernel PR #3095
+Run: https://github.com/kernel/kernel/actions/runs/30825504791
+Branch: stlc/integration-test/pr-3095