fix(update): launch installers after the current app exits

src/main/main.ts

@@ -403,7 +403,7 @@ function registerIpcHandlers(): void {
     if (result.started) {
       updateQuitTimer = setTimeout(() => {
         app.quit();
-      }, 5000);
+      }, 250);
     }
     return result;
   });

src/main/update.ts

@@ -893,9 +893,38 @@ async function resolveDigestFromYml(repo: string, tag: string, setupName: string
   return "";
 }
 
-export function buildInstallerLaunchArgs(): string[] {
-  return ["/S", "--updated", "--force-run"];
-}
+export function buildInstallerLaunchArgs(): string[] {
+  return ["/S", "--updated", "--force-run"];
+}
+
+function quotePowerShellLiteral(value: string): string {
+  return `'${value.replaceAll("'", "''")}'`;
+}
+
+export function buildDeferredInstallerLaunch(
+  targetPath: string,
+  currentProcessId: number = process.pid,
+  systemRoot: string = process.env.SystemRoot || "C:\\Windows"
+): { command: string; args: string[] } {
+  const installerArgs = buildInstallerLaunchArgs().map(quotePowerShellLiteral).join(",");
+  const script = [
+    "$deadline=(Get-Date).AddMinutes(2)",
+    `while ((Get-Process -Id ${Math.max(1, Math.floor(currentProcessId))} -ErrorAction SilentlyContinue) -and ((Get-Date) -lt $deadline)) { Start-Sleep -Milliseconds 200 }`,
+    `Start-Process -FilePath ${quotePowerShellLiteral(targetPath)} -ArgumentList @(${installerArgs}) -WindowStyle Hidden`
+  ].join("; ");
+  return {
+    command: path.win32.join(systemRoot, "System32", "WindowsPowerShell", "v1.0", "powershell.exe"),
+    args: [
+      "-NoLogo",
+      "-NoProfile",
+      "-NonInteractive",
+      "-WindowStyle",
+      "Hidden",
+      "-EncodedCommand",
+      Buffer.from(script, "utf16le").toString("base64")
+    ]
+  };
+}
 
 export async function checkGitHubUpdate(repo: string): Promise<UpdateCheckResult> {
   const safeRepo = normalizeUpdateRepo(repo);
@@ -1097,13 +1126,14 @@ export async function installLatestUpdate(
       message: "Starte stille Update-Installation",
     });
 
-    const child = childProcess.spawn(targetPath, buildInstallerLaunchArgs(), {
-      detached: true,
-      stdio: "ignore",
-      windowsHide: true,
-    });
-    child.once("error", (spawnError) => {
-      logger.error(`Update-Installer Start fehlgeschlagen: ${compactErrorText(spawnError)}`);
+    const deferredLaunch = buildDeferredInstallerLaunch(targetPath);
+    const child = childProcess.spawn(deferredLaunch.command, deferredLaunch.args, {
+      detached: true,
+      stdio: "ignore",
+      windowsHide: true,
+    });
+    child.once("error", (spawnError) => {
+      logger.error(`Update-Launcher Start fehlgeschlagen: ${compactErrorText(spawnError)}`);
     });
     child.unref();