[#451] added websocket connexion (#453)

* [#451] added websocket connexion

* [#451] added tests

* [#451] add missing cleanup for web socket causing memory leaks

__test__/features/websocket/api/fetchWebSocketTicket.test.tsx

@@ -0,0 +1,46 @@
+import { api } from "../../../../src/utils/apiUtils";
+import { fetchWebSocketTicket } from "../../../../src/websocket/api/fetchWebSocketTicket";
+
+jest.mock("../../../../src/utils/apiUtils");
+
+describe("fetchWebSocketTicket", () => {
+  const mockTicket = {
+    clientAddress: "127.0.0.1",
+    value: "test-ticket-123",
+    generatedOn: "2025-01-12T10:00:00Z",
+    validUntil: "2025-01-12T11:00:00Z",
+    username: "testuser",
+  };
+
+  beforeEach(() => {
+    jest.clearAllMocks();
+  });
+
+  it("should fetch ticket successfully", async () => {
+    (api.post as jest.Mock).mockResolvedValue({
+      ok: true,
+      json: async () => mockTicket,
+    });
+
+    const ticket = await fetchWebSocketTicket();
+
+    expect(api.post).toHaveBeenCalledWith("ws/ticket");
+    expect(ticket).toEqual(mockTicket);
+  });
+
+  it("should throw error when response is not ok", async () => {
+    (api.post as jest.Mock).mockResolvedValue({
+      ok: false,
+    });
+
+    await expect(fetchWebSocketTicket()).rejects.toThrow(
+      "Failed to fetch WebSocket ticket"
+    );
+  });
+
+  it("should throw error when network fails", async () => {
+    (api.post as jest.Mock).mockRejectedValue(new Error("Network error"));
+
+    await expect(fetchWebSocketTicket()).rejects.toThrow("Network error");
+  });
+});