fix(cli): hide Windows daemon consoles

Hide detached CLI and dashboard daemon windows, and prevent taskkill from flashing a console while replacing or closing sessions. Browser process launches remain unchanged so headed mode, Inspector, and UI mode stay visible.\n\nFixes: https://github.com/microsoft/playwright/issues/42152\n\nCo-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>\nCopilot-Session: 37896276-261f-4ff0-9664-06aa7dfc471b

Author: Skn0tt

packages/playwright-core/src/tools/backend/devtools.ts

@@ -135,7 +135,7 @@ const annotate = defineTabTool({
     const daemonArgs = [daemonScript, `--pageId=${pageId}`];
 
     // Spawn the dashboard daemon (idempotent — the singleton socket guards against duplicates).
-    const daemon = spawn(process.execPath, daemonArgs, { detached: true, stdio: 'ignore' });
+    const daemon = spawn(process.execPath, daemonArgs, { detached: true, stdio: 'ignore', windowsHide: true });
     daemon.unref();
 
     // Spawn the annotate client in JSON mode to capture the raw payload over stdout.

packages/playwright-core/src/tools/cli-client/program.ts

@@ -248,6 +248,7 @@ export async function program(options?: { embedderVersion?: string}) {
       const child = spawn(process.execPath, daemonArgs, {
         detached: !foreground,
         stdio: foreground ? 'inherit' : ['pipe', 'pipe', 'ignore'],
+        windowsHide: true,
       });
       if (foreground) {
         await new Promise<void>(resolve => child.on('exit', () => resolve()));

packages/playwright-core/src/tools/cli-client/session.ts

@@ -148,6 +148,7 @@ export class Session {
       detached: true,
       stdio: ['ignore', 'pipe', err],
       cwd: process.cwd(), // Will be used as root.
+      windowsHide: true,
     });
 
     let signalled = false;

packages/utils/processLauncher.ts

@@ -233,7 +233,7 @@ export async function launchProcess(options: LaunchProcessOptions): Promise<Laun
       // Force kill the browser.
       try {
         if (process.platform === 'win32') {
-          const taskkillProcess = childProcess.spawnSync(`taskkill /pid ${spawnedProcess.pid} /T /F`, { shell: true });
+          const taskkillProcess = childProcess.spawnSync(`taskkill /pid ${spawnedProcess.pid} /T /F`, { shell: true, windowsHide: true });
           const [stdout, stderr] = [taskkillProcess.stdout.toString(), taskkillProcess.stderr.toString()];
           if (stdout)
             options.log(`[pid=${spawnedProcess.pid}] taskkill stdout: ${stdout}`);