add shim, basic stubs

shims/electron/web-frame.js

@@ -0,0 +1,27 @@
+// Shim for electron.webFrame
+// Obsidian uses: getZoomLevel(), setZoomLevel()
+
+let currentZoom = 0;
+
+export const webFrame = {
+  getZoomLevel() {
+    return currentZoom;
+  },
+
+  setZoomLevel(level) {
+    currentZoom = level;
+    // Approximate Electron's zoom behavior via CSS zoom
+    // Electron zoom level 0 = 100%, each step is ~20%
+    const scale = Math.pow(1.2, level);
+    document.body.style.zoom = scale;
+  },
+
+  getZoomFactor() {
+    return Math.pow(1.2, currentZoom);
+  },
+
+  setZoomFactor(factor) {
+    currentZoom = Math.log(factor) / Math.log(1.2);
+    document.body.style.zoom = factor;
+  },
+};