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/services/polling-service.ts

@@ -0,0 +1,92 @@
+/**
+ * Polling Service - Simplified version
+ * Uses strategy pattern for different polling behaviors
+ */
+
+import type { ExtensionLogger } from '../utils/logger';
+import type { TaskRepository } from './task-repository';
+
+export interface PollingStrategy {
+	calculateNextInterval(
+		consecutiveNoChanges: number,
+		lastChangeTime?: number
+	): number;
+	getName(): string;
+}
+
+export class PollingService {
+	private timer?: NodeJS.Timeout;
+	private consecutiveNoChanges = 0;
+	private lastChangeTime?: number;
+	private lastTasksJson?: string;
+
+	constructor(
+		private repository: TaskRepository,
+		private strategy: PollingStrategy,
+		private logger: ExtensionLogger
+	) {}
+
+	start(): void {
+		if (this.timer) {
+			return;
+		}
+
+		this.logger.log(
+			`Starting polling with ${this.strategy.getName()} strategy`
+		);
+		this.scheduleNextPoll();
+	}
+
+	stop(): void {
+		if (this.timer) {
+			clearTimeout(this.timer);
+			this.timer = undefined;
+			this.logger.log('Polling stopped');
+		}
+	}
+
+	setStrategy(strategy: PollingStrategy): void {
+		this.strategy = strategy;
+		this.logger.log(`Changed to ${strategy.getName()} polling strategy`);
+
+		// Restart with new strategy if running
+		if (this.timer) {
+			this.stop();
+			this.start();
+		}
+	}
+
+	private async poll(): Promise<void> {
+		try {
+			const tasks = await this.repository.getAll();
+			const tasksJson = JSON.stringify(tasks);
+
+			// Check for changes
+			if (tasksJson !== this.lastTasksJson) {
+				this.consecutiveNoChanges = 0;
+				this.lastChangeTime = Date.now();
+				this.logger.debug('Tasks changed');
+			} else {
+				this.consecutiveNoChanges++;
+			}
+
+			this.lastTasksJson = tasksJson;
+		} catch (error) {
+			this.logger.error('Polling error', error);
+		}
+	}
+
+	private scheduleNextPoll(): void {
+		const interval = this.strategy.calculateNextInterval(
+			this.consecutiveNoChanges,
+			this.lastChangeTime
+		);
+
+		this.timer = setTimeout(async () => {
+			await this.poll();
+			this.scheduleNextPoll();
+		}, interval);
+
+		this.logger.debug(`Next poll in ${interval}ms`);
+	}
+}