add e2e tests for all image tools

src/pages/image/png/create-transparent/create-transparent.e2e.spec.ts

@@ -0,0 +1,40 @@
+import { expect, test } from '@playwright/test';
+import { Buffer } from 'buffer';
+import path from 'path';
+import Jimp from 'jimp';
+
+test.describe('Create transparent PNG', () => {
+  test.beforeEach(async ({ page }) => {
+    await page.goto('/png/create-transparent');
+  });
+
+  test('should make png color transparent', async ({ page }) => {
+    // Upload image
+    const fileInput = page.locator('input[type="file"]');
+    const imagePath = path.join(__dirname, 'test.png');
+    await fileInput?.setInputFiles(imagePath);
+
+    await page.getByTestId('color-input').fill('#FF0000');
+
+    // Click on download
+    const downloadPromise = page.waitForEvent('download');
+    await page.getByText('Save as').click();
+
+    // Intercept and read downloaded PNG
+    const download = await downloadPromise;
+    const downloadStream = await download.createReadStream();
+
+    const chunks = [];
+    for await (const chunk of downloadStream) {
+      chunks.push(chunk);
+    }
+    const fileContent = Buffer.concat(chunks);
+
+    expect(fileContent.length).toBeGreaterThan(0);
+
+    // Check that the first pixel is transparent
+    const image = await Jimp.read(fileContent);
+    const color = image.getPixelColor(0, 0);
+    expect(color).toBe(0);
+  });
+});