Initial commit: Complete Shopify Price Updater implementation

- Full Node.js application with Shopify GraphQL API integration
- Compare At price support for promotional pricing
- Comprehensive error handling and retry logic
- Progress tracking with markdown logging
- Complete test suite with unit and integration tests
- Production-ready with proper exit codes and signal handling

test-progress-service.js

@@ -0,0 +1,81 @@
+const ProgressService = require("./src/services/progress");
+const fs = require("fs").promises;
+
+async function testProgressService() {
+	console.log("Testing Progress Service...");
+
+	// Use a test file to avoid interfering with actual progress
+	const testFilePath = "test-progress.md";
+	const progressService = new ProgressService(testFilePath);
+
+	try {
+		// Clean up any existing test file
+		try {
+			await fs.unlink(testFilePath);
+		} catch (error) {
+			// File doesn't exist, that's fine
+		}
+
+		// Test 1: Log operation start
+		console.log("✓ Testing operation start logging...");
+		await progressService.logOperationStart({
+			targetTag: "test-tag",
+			priceAdjustmentPercentage: 10,
+		});
+
+		// Test 2: Log successful product update
+		console.log("✓ Testing product update logging...");
+		await progressService.logProductUpdate({
+			productId: "gid://shopify/Product/123",
+			productTitle: "Test Product",
+			variantId: "gid://shopify/ProductVariant/456",
+			oldPrice: 10.0,
+			newPrice: 11.0,
+		});
+
+		// Test 3: Log error
+		console.log("✓ Testing error logging...");
+		await progressService.logError({
+			productId: "gid://shopify/Product/789",
+			productTitle: "Failed Product",
+			variantId: "gid://shopify/ProductVariant/101",
+			errorMessage: "Invalid price data",
+		});
+
+		// Test 4: Log completion summary
+		console.log("✓ Testing completion summary...");
+		await progressService.logCompletionSummary({
+			totalProducts: 2,
+			successfulUpdates: 1,
+			failedUpdates: 1,
+			startTime: new Date(Date.now() - 5000), // 5 seconds ago
+		});
+
+		// Verify file was created and has content
+		const content = await fs.readFile(testFilePath, "utf8");
+		console.log("✓ Progress file created successfully");
+		console.log("✓ File contains:", content.length, "characters");
+
+		// Test timestamp formatting
+		const timestamp = progressService.formatTimestamp(
+			new Date("2024-01-01T12:00:00.000Z")
+		);
+		console.log("✓ Timestamp format test:", timestamp);
+
+		// Clean up test file
+		await fs.unlink(testFilePath);
+		console.log("✓ Test file cleaned up");
+
+		console.log("\n🎉 All Progress Service tests passed!");
+	} catch (error) {
+		console.error("❌ Test failed:", error.message);
+		// Clean up test file even if tests fail
+		try {
+			await fs.unlink(testFilePath);
+		} catch (cleanupError) {
+			// Ignore cleanup errors
+		}
+	}
+}
+
+testProgressService();