feat(desktop): add preload script and pnpm build approvals

surfsense_desktop/pnpm-workspace.yaml

@@ -0,0 +1,4 @@
+onlyBuiltDependencies:
+  - electron
+  - electron-winstaller
+  - esbuild

surfsense_desktop/src/preload.ts

@@ -0,0 +1,19 @@
+const { contextBridge, ipcRenderer } = require('electron');
+
+contextBridge.exposeInMainWorld('electronAPI', {
+  versions: {
+    electron: process.versions.electron,
+    node: process.versions.node,
+    chrome: process.versions.chrome,
+    platform: process.platform,
+  },
+  openExternal: (url: string) => ipcRenderer.send('open-external', url),
+  getAppVersion: () => ipcRenderer.invoke('get-app-version'),
+  onDeepLink: (callback: (url: string) => void) => {
+    const listener = (_event: unknown, url: string) => callback(url);
+    ipcRenderer.on('deep-link', listener);
+    return () => {
+      ipcRenderer.removeListener('deep-link', listener);
+    };
+  },
+});