fix(onboard): preserve --add-host on GPU sandbox recreate (#3562)

src/lib/onboard/docker-gpu-patch.test.ts

@@ -214,7 +214,10 @@ describe("docker-gpu-patch", () => {
     expect(args).toEqual(
       expect.arrayContaining(["--env", "OPENSHELL_ENDPOINT=http://127.0.0.1:8080/"]),
     );
-    expect(args).not.toEqual(
+    // --add-host writes to /etc/hosts (mount namespace), not the network
+    // stack, so it must survive even when --network=host is explicitly
+    // requested (#3562, #3568).
+    expect(args).toEqual(
       expect.arrayContaining(["--add-host", "host.openshell.internal:172.17.0.1"]),
     );
     expect(args).not.toEqual(expect.arrayContaining(["--network-alias", "openshell-alpha"]));
@@ -226,7 +229,7 @@ describe("docker-gpu-patch", () => {
   });
 
   it("reports the Docker GPU patch network mode", () => {
-    expect(getDockerGpuPatchNetworkMode({})).toBe("host");
+    expect(getDockerGpuPatchNetworkMode({})).toBe("preserve");
     expect(getDockerGpuPatchNetworkMode({ NEMOCLAW_DOCKER_GPU_PATCH_NETWORK: "host" })).toBe(
       "host",
     );
@@ -394,9 +397,11 @@ describe("docker-gpu-patch", () => {
         "--security-opt",
         "apparmor=unconfined",
         "--network",
-        "host",
+        "openshell-docker",
+        "--add-host",
+        "host.openshell.internal:172.17.0.1",
         "--env",
-        "OPENSHELL_ENDPOINT=http://127.0.0.1:8080/",
+        "OPENSHELL_ENDPOINT=http://host.openshell.internal:8080/",
       ]),
       expect.objectContaining({ ignoreError: true }),
     );

src/lib/onboard/docker-gpu-patch.ts

@@ -358,9 +358,9 @@ export function getDockerGpuPatchNetworkMode(
   env: Record<string, string | undefined> = process.env,
 ): "host" | "preserve" {
   const networkOverride = String(env[DOCKER_GPU_PATCH_NETWORK_ENV] || "").trim().toLowerCase();
+  if (networkOverride === "host") return "host";
   if (networkOverride === "preserve" || networkOverride === "bridge") return "preserve";
-  if (networkOverride && networkOverride !== "host") return "preserve";
-  return "host";
+  return "preserve";
 }
 
 function dockerNetworkAliases(
@@ -449,9 +449,11 @@ export function buildDockerGpuCloneRunArgs(
     securityOpt.add("apparmor=unconfined");
   }
   for (const opt of securityOpt) args.push("--security-opt", opt);
-  if (networkMode !== "host") {
-    for (const hostEntry of stringArray(host.ExtraHosts)) args.push("--add-host", hostEntry);
-  }
+  // --add-host writes to the container's /etc/hosts (mount namespace), not
+  // the network stack, so OpenShell's host.openshell.internal mapping must
+  // survive even when the caller explicitly opts into --network=host via
+  // NEMOCLAW_DOCKER_GPU_PATCH_NETWORK=host (#3562, #3568).
+  for (const hostEntry of stringArray(host.ExtraHosts)) args.push("--add-host", hostEntry);
   for (const group of stringArray(host.GroupAdd)) args.push("--group-add", group);
   if (networkMode !== "host") {
     for (const dns of stringArray(host.Dns)) args.push("--dns", dns);