Fix print null errors and add main process logging to renderer console

- Added null checks for toolbar, tab-bar, status-bar before accessing .style
- Prevents TypeError when elements don't exist
- Added executeJavaScript to send main process logs to renderer console
- Now we can see main process state in DevTools
- Print should now work without errors

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

test-file-open.md

@@ -0,0 +1,14 @@
+# Test File Opening
+
+This is a test file to verify that double-click file opening works correctly.
+
+## Features
+- **Bold text**
+- *Italic text*
+- `Code`
+
+```javascript
+console.log("Hello World");
+```
+
+This should appear when you double-click to open the file!