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/utils/event-emitter.ts

@@ -0,0 +1,34 @@
+/**
+ * Simple Event Emitter
+ * Lightweight alternative to complex event bus
+ */
+
+export type EventHandler = (...args: any[]) => void | Promise<void>;
+
+export class EventEmitter {
+	private handlers = new Map<string, Set<EventHandler>>();
+
+	on(event: string, handler: EventHandler): () => void {
+		if (!this.handlers.has(event)) {
+			this.handlers.set(event, new Set());
+		}
+		this.handlers.get(event)?.add(handler);
+
+		// Return unsubscribe function
+		return () => this.off(event, handler);
+	}
+
+	off(event: string, handler: EventHandler): void {
+		this.handlers.get(event)?.delete(handler);
+	}
+
+	emit(event: string, ...args: any[]): void {
+		this.handlers.get(event)?.forEach((handler) => {
+			try {
+				handler(...args);
+			} catch (error) {
+				console.error(`Error in event handler for ${event}:`, error);
+			}
+		});
+	}
+}