test(e2e): add notification bell mark-as-read flow

tests/e2e/notifications.spec.ts

@@ -0,0 +1,58 @@
+import { test, expect } from "@playwright/test";
+
+test.describe("Notification Bell", () => {
+  test.beforeEach(async ({ page }) => {
+    await page.addInitScript(() => {
+      localStorage.setItem("onboarding_tour_dismissed", "1");
+    });
+
+    await page.goto("/");
+  });
+
+  test("should open notification dropdown, mark one read, and decrement unread count", async ({ page }) => {
+    const connectButton = page.getByRole("button", { name: /Connect Wallet/i }).first();
+    await expect(connectButton).toBeVisible();
+    await connectButton.click();
+    await expect(page.getByText(/Connected/i).first()).toBeVisible();
+
+    await page.goto("/en/causes/1");
+    await expect(page.getByRole("heading", { name: /Clean Water/i })).toBeVisible({ timeout: 10000 });
+
+    const fundButton = page.getByRole("button", { name: /Fund This Cause/i }).first();
+    await expect(fundButton).toBeVisible();
+    await fundButton.click();
+
+    const dialog = page.getByRole("dialog");
+    await expect(dialog).toBeVisible();
+
+    const amountInput = dialog.getByLabel(/Amount/i);
+    await amountInput.fill("10");
+
+    const donateButton = dialog.getByRole("button", { name: /Donate 10 XLM/i });
+    await expect(donateButton).toBeEnabled();
+    await donateButton.scrollIntoViewIfNeeded();
+    await donateButton.click();
+
+    await expect(page.getByText(/donated successfully/i)).toBeVisible({ timeout: 15000 });
+    await page.getByRole("button", { name: /Close/i }).click();
+
+    const bell = page.getByRole("button", { name: /Notifications/ });
+    await expect(bell).toBeVisible();
+    const badge = bell.getByText(/\d+/);
+    await expect(badge).toBeVisible();
+    const initialCount = await badge.textContent();
+
+    await bell.click();
+    const dropdown = page.getByRole("dialog", { name: /Notifications/i });
+    await expect(dropdown).toBeVisible();
+
+    const markReadButton = dropdown.getByRole("button", { name: /Mark notification/i }).first();
+    await expect(markReadButton).toBeVisible();
+    await markReadButton.click();
+
+    await page.keyboard.press("Escape");
+    await expect(dropdown).not.toBeVisible();
+
+    await expect(badge).not.toHaveText(initialCount ?? "", { timeout: 5000 });
+  });
+});