fix: add windowsHide to browse detached server spawn on Windows

browse/src/cli.ts

@@ -285,6 +285,7 @@ function raiseHeadedWindowMacOS(): void {
     nodeSpawn('osascript', ['-e', 'tell application "Google Chrome for Testing" to activate'], {
       stdio: 'ignore',
       detached: true,
+      windowsHide: true,
     }).unref();
   } catch {
     // osascript missing or app not present — non-fatal
@@ -323,7 +324,7 @@ async function startServer(extraEnv?: Record<string, string>): Promise<ServerSta
     const launcherCode =
       `const{spawn}=require('child_process');` +
       `spawn(process.execPath,[${JSON.stringify(NODE_SERVER_SCRIPT)}],` +
-      `{detached:true,stdio:['ignore','ignore','ignore'],env:Object.assign({},process.env,` +
+      `{detached:true,windowsHide:true,stdio:['ignore','ignore','ignore'],env:Object.assign({},process.env,` +
       `${extraEnvStr})}).unref()`;
     Bun.spawnSync(['node', '-e', launcherCode], { stdio: ['ignore', 'ignore', 'ignore'] });
   } else {
@@ -340,6 +341,7 @@ async function startServer(extraEnv?: Record<string, string>): Promise<ServerSta
     // the Windows path's rationale — same root cause, different OS API.
     nodeSpawn('bun', ['run', SERVER_SCRIPT], {
       detached: true,
+      windowsHide: true,
       stdio: ['ignore', 'ignore', 'ignore'],
       env: { ...process.env, BROWSE_STATE_FILE: config.stateFile, BROWSE_PARENT_PID: parentPid, ...extraEnv },
     }).unref();

browse/test/cli-windows-hide.test.ts

@@ -0,0 +1,36 @@
+import { describe, expect, test } from "bun:test";
+import * as fs from "node:fs";
+import * as path from "node:path";
+
+const ROOT = path.resolve(import.meta.dir, "..", "..");
+const CLI = path.join(ROOT, "browse", "src", "cli.ts");
+
+function readCodeOnly(): string {
+  return fs.readFileSync(CLI, "utf-8")
+    .split("\n")
+    .filter((line) => !line.trim().startsWith("//"))
+    .join("\n");
+}
+
+// #1835 tripwire. On Windows, detached child_process.spawn allocates a
+// console window unless windowsHide:true is set. These static checks fail CI
+// if any detached spawn path in cli.ts drops the Windows no-window flag.
+describe("#1835 detached browse spawns hide Windows consoles", () => {
+  test("Windows Node launcher spawn carries windowsHide:true", () => {
+    const src = readCodeOnly();
+    expect(src).toMatch(/spawn\(process\.execPath,[\s\S]{0,500}detached:\s*true[\s\S]{0,100}windowsHide:\s*true/);
+  });
+
+  test("non-Windows server nodeSpawn carries windowsHide:true", () => {
+    const src = readCodeOnly();
+    expect(src).toMatch(/nodeSpawn\('bun',[\s\S]{0,500}detached:\s*true[\s\S]{0,100}windowsHide:\s*true/);
+  });
+
+  test("every detached spawn site in cli.ts carries windowsHide:true", () => {
+    const src = readCodeOnly();
+    const detachedSpawns = src.match(/detached:\s*true/g)?.length ?? 0;
+    const windowsHideFlags = src.match(/windowsHide:\s*true/g)?.length ?? 0;
+    expect(detachedSpawns).toBeGreaterThan(0);
+    expect(windowsHideFlags).toBeGreaterThanOrEqual(detachedSpawns);
+  });
+});