ci(parity): emulación QEMU arm64 en el lane runtime

Los casos up.update-uid-arm64* / arm64v8* arrancan contenedores arm64
reales; en el runner amd64 quedaban inconclusive por exec-format. Registrar
binfmt via docker/setup-qemu-action los hace ejecutables y comparables.

- go-cli.yml: docker/setup-qemu-action@v3 (platforms: arm64) en parity-runtime.
- parity_matrix_test.go: runtimeTimeout overridable por PARITY_RUNTIME_TIMEOUT;
  CI lo fija en 10m para dar aire a la emulación (lenta) sin frenar amd64.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: aledbf

.github/workflows/go-cli.yml

@@ -101,10 +101,18 @@ jobs:
   parity-runtime:
     runs-on: ubuntu-latest
     needs: lint-and-test
+    env:
+      # Los casos update-uid-arm64* arrancan contenedores arm64 reales; en un
+      # runner amd64 se ejecutan emulados vía QEMU (binfmt), que es lento.
+      PARITY_RUNTIME_TIMEOUT: "10m"
     steps:
       - uses: actions/checkout@v7
         with:
           submodules: recursive
+      - name: Set up QEMU (emulación arm64)
+        uses: docker/setup-qemu-action@v3
+        with:
+          platforms: arm64
       - uses: actions/setup-go@v6
         with:
           go-version-file: go.mod

internal/cli/parity_matrix_test.go

@@ -196,7 +196,15 @@ func TestParityMatrix(t *testing.T) {
 	cliTS := envOr("CLI_TS", "node "+filepath.Join(repoRoot, "reference", "devcontainer.js"))
 	cliGO := envOr("CLI_GO", filepath.Join(repoRoot, "devcontainer"))
 	defaultTimeout := 60 * time.Second
+	// Runtime lane default; overridable via PARITY_RUNTIME_TIMEOUT (e.g. "10m")
+	// so CI can grant headroom to QEMU-emulated arm64 cases without slowing the
+	// amd64 cases here.
 	runtimeTimeout := 300 * time.Second
+	if v := os.Getenv("PARITY_RUNTIME_TIMEOUT"); v != "" {
+		if d, err := time.ParseDuration(v); err == nil {
+			runtimeTimeout = d
+		}
+	}
 
 	// Check TS CLI exists
 	if _, err := os.Stat(filepath.Join(repoRoot, "reference", "dist", "spec-node", "devContainersSpecCLI.js")); err != nil {