add Confidential Computing readiness check + collect nvidia-smi conf-compute -q

New read-only "Check" step reports whether this server can run NVIDIA
Confidential Computing: CPU TEE support (Intel TDX / AMD SEV-SNP, via
dmesg and kvm_amd sysfs params) and GPU firmware CC capability (via
`nvidia-smi conf-compute -q`). Also collect that command's output into
the techdump export bundle.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

audit/internal/webui/task_runner.go

@@ -272,6 +272,12 @@ func executeTaskWithOptions(opts *HandlerOptions, t *Task, j *jobState, ctx cont
 			break
 		}
 		archive, err = runStorageAcceptancePackCtx(a, ctx, "", t.params.StressMode, j.append)
+	case "confidential-computing":
+		if a == nil {
+			err = fmt.Errorf("app not configured")
+			break
+		}
+		archive, err = runConfidentialComputingCheckPackCtx(a, ctx, "", j.append)
 	case "cpu":
 		if a == nil {
 			err = fmt.Errorf("app not configured")