feat(extension): complete VS Code extension with kanban board interface (#997)

---------
Co-authored-by: DavidMaliglowka <13022280+DavidMaliglowka@users.noreply.github.com>
Co-authored-by: Ralph Khreish <35776126+Crunchyman-ralph@users.noreply.github.com>
Co-authored-by: coderabbitai[bot] <136622811+coderabbitai[bot]@users.noreply.github.com>

apps/extension/src/webview/index.tsx

@@ -0,0 +1,28 @@
+/**
+ * Webview Entry Point
+ */
+
+import React from 'react';
+import { createRoot } from 'react-dom/client';
+import { App } from './App';
+// CSS is built separately by Tailwind
+
+// VS Code API declaration
+declare global {
+	interface Window {
+		acquireVsCodeApi?: () => {
+			postMessage: (message: any) => void;
+			setState: (state: any) => void;
+			getState: () => any;
+		};
+	}
+}
+
+// Initialize React app
+const container = document.getElementById('root');
+if (container) {
+	const root = createRoot(container);
+	root.render(<App />);
+} else {
+	console.error('❌ Root container not found');
+}