feat(sprint-6): Phase 6 — Notifications (WebSocket) + PWA

- WebSocket: Spring STOMP + SockJS, NotificationService, persistent notifications table
- NotificationController: GET/PUT endpoints for notification management
- Frontend: notification bell with unread badge, dropdown panel, real-time via STOMP
- PWA: manifest.json, service worker (manual sw.js), offline page, install prompt
- PWA icons (192+512), dark theme colors, standalone display
- Full i18n (de/en) for notifications and PWA
- Flyway V10 migration for notifications table
- spring-boot-starter-websocket dependency added

cannamanage-frontend/e2e/functional-flows.spec.ts

@@ -59,9 +59,9 @@ test.describe("Group 1: Login Form Interactions", () => {
     expect(page.url()).toContain("/login")
 
     // The email input should fail native HTML5 validation
-    const isInvalid = await page.locator('input[id="email"]').evaluate(
-      (el: HTMLInputElement) => !el.checkValidity()
-    )
+    const isInvalid = await page
+      .locator('input[id="email"]')
+      .evaluate((el: HTMLInputElement) => !el.checkValidity())
     expect(isInvalid).toBe(true)
   })
 
@@ -192,7 +192,9 @@ test.describe("Group 3: Navigation & Layout", () => {
     const url = page.url()
     // If redirected to login — that's also acceptable behavior for protected routes
     const is404OrLogin = url.includes("/login") || url.includes("not-found")
-    expect(is404OrLogin || (await page.locator("body").textContent()) !== "").toBe(true)
+    expect(
+      is404OrLogin || (await page.locator("body").textContent()) !== ""
+    ).toBe(true)
   })
 
   test("3.3 - Responsive: mobile viewport (375px)", async ({ page }) => {
@@ -611,9 +613,7 @@ test.describe("Group 11: Accessibility Basics", () => {
     await expect(emailInput).toHaveAttribute("autoComplete", "email")
   })
 
-  test("11.5 - Form submit button is keyboard-accessible", async ({
-    page,
-  }) => {
+  test("11.5 - Form submit button is keyboard-accessible", async ({ page }) => {
     await page.goto("/login", { waitUntil: "domcontentloaded" })
     await page.waitForSelector('input[id="email"]', { timeout: 15000 })
 
@@ -683,7 +683,8 @@ test.describe("Group 12: Error States & Edge Cases", () => {
 
     // Page should not crash — wait and verify it's still functional
     await page.waitForTimeout(3000)
-    const isStillOnLogin = page.url().includes("/login") || page.url().includes("/dashboard")
+    const isStillOnLogin =
+      page.url().includes("/login") || page.url().includes("/dashboard")
     expect(isStillOnLogin).toBe(true)
   })