feat(launcher): bundle Bun and use it across all launchers (#243)

src/main/runtime/prepare-launcher-runtime.ts

@@ -0,0 +1,24 @@
+import fs from 'node:fs';
+import path from 'node:path';
+import { cleanupOldWindowsManagedRuntimes, stageManagedLauncher } from './managed-launcher';
+
+// Bundled separately as Node-compatible code so AppImages can prepare their
+// runtime without starting Electron's GUI, single-instance lock, or settings.
+export function prepareLauncherRuntime(options: { appPath: string; resourcesPath: string }) {
+  const appVersion = fs
+    .readFileSync(path.join(options.resourcesPath, 'launcher', 'version'), 'utf8')
+    .trim();
+  const payload = stageManagedLauncher({
+    appExePath: options.appPath,
+    appVersion,
+    bundledBunPath: path.join(
+      options.resourcesPath,
+      'bun',
+      process.platform === 'win32' ? 'bun.exe' : 'bun',
+    ),
+    launcherResourcePath: path.join(options.resourcesPath, 'launcher', 'subminer.js'),
+    force: process.platform === 'linux',
+  });
+  if (process.platform === 'win32') cleanupOldWindowsManagedRuntimes({ appVersion });
+  return payload;
+}