test(ui): migrate suite to the app-shell (state-driven navigation)

- Unit: repoint moved screen imports (lib/screens, lib/game), mock
  $lib/app-nav (appScreen/activeView) instead of $app/navigation, drop the
  removed gameId props, assert screen/view selection.
- e2e: add a dev-only window.__galaxyNav affordance; specs enter a game via
  enterGame(...) instead of a /games/:id URL; URL assertions become content
  assertions (the URL stays /game/); reload uses waitUntil:"commit" (shallow
  routing) and mocks /rpc on game entry.
- Remove the obsolete report scroll-restore test (it relied on a SvelteKit
  route Snapshot that no longer exists); update the missing-membership test
  to the new lobby-redirect+toast behaviour. Fix a stale report.svelte
  docstring.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

ui/frontend/tests/lobby-page.test.ts

@@ -1,11 +1,14 @@
-// Component tests for the Phase 8 lobby page. The lobby API and the
+// Component tests for the Phase 8 lobby screen. The lobby API and the
 // gateway client are mocked at module level; the session singleton is
 // wired to a per-test `SessionStore`-backing IndexedDB so the page's
 // boot path settles on `authenticated` and constructs a real
 // GalaxyClient (which is then never called because the lobby API
 // wrappers are stubs). The tests assert the section rendering, the
 // inline race-name form for public games, and the invitation Accept
-// flow.
+// flow. The app-shell navigation store is mocked so opening a game
+// (`activeView.reset()` + `appScreen.go("game", …)`) or the create
+// form (`appScreen.go("lobby-create")`) never runs real `pushState`
+// in JSDOM; the single-URL shell has no `/lobby`/`/games` routes.
 
 import "fake-indexeddb/auto";
 import { fireEvent, render, waitFor } from "@testing-library/svelte";
@@ -25,8 +28,19 @@ import { type GalaxyDB, openGalaxyDB } from "../src/platform/store/idb";
 import { IDBCache } from "../src/platform/store/idb-cache";
 import { WebCryptoKeyStore } from "../src/platform/store/webcrypto-keystore";
 
-vi.mock("$app/navigation", () => ({
-	goto: vi.fn(async () => {}),
+// The lobby screen navigates through the app-shell stores
+// (`appScreen.go`, `activeView.reset`/`select`), which internally call
+// SvelteKit `pushState`. Mock the whole nav module so the spies
+// capture the transitions and no real history mutation runs in JSDOM.
+const appScreenGoSpy = vi.fn();
+const activeViewResetSpy = vi.fn();
+const activeViewSelectSpy = vi.fn();
+vi.mock("$lib/app-nav.svelte", () => ({
+	appScreen: { go: (...args: unknown[]) => appScreenGoSpy(...args) },
+	activeView: {
+		reset: (...args: unknown[]) => activeViewResetSpy(...args),
+		select: (...args: unknown[]) => activeViewSelectSpy(...args),
+	},
 }));
 
 const listMyGamesSpy = vi.fn();
@@ -105,6 +119,9 @@ beforeEach(async () => {
 	submitApplicationSpy.mockReset();
 	redeemInviteSpy.mockReset();
 	declineInviteSpy.mockReset();
+	appScreenGoSpy.mockReset();
+	activeViewResetSpy.mockReset();
+	activeViewSelectSpy.mockReset();
 });
 
 afterEach(async () => {
@@ -119,8 +136,10 @@ afterEach(async () => {
 	});
 });
 
-async function importLobbyPage(): Promise<typeof import("../src/routes/lobby/+page.svelte")> {
-	return import("../src/routes/lobby/+page.svelte");
+async function importLobbyPage(): Promise<
+	typeof import("../src/lib/screens/lobby-screen.svelte")
+> {
+	return import("../src/lib/screens/lobby-screen.svelte");
 }
 
 const baseDate = new Date("2026-05-07T10:00:00Z");
@@ -184,7 +203,7 @@ function makeApplication(id: string, status: string) {
 	};
 }
 
-describe("lobby page", () => {
+describe("lobby screen", () => {
 	test("renders empty states for every section when API returns no items", async () => {
 		listMyGamesSpy.mockResolvedValue([]);
 		listPublicGamesSpy.mockResolvedValue({ items: [], page: 1, pageSize: 50, total: 0 });
@@ -375,6 +394,18 @@ describe("lobby page", () => {
 		expect(disabledByLabel["Closed Run"]).toBe(false);
 		expect(disabledByLabel["Cancelled Run"]).toBe(true);
 		expect(disabledByLabel["Draft Run"]).toBe(true);
+
+		// Clicking a playable card resets the in-game view and enters the
+		// game screen with its id (the single-URL app-shell switches
+		// in-memory state instead of navigating to `/games/:id`).
+		const liveCard = cards.find(
+			(card) => card.querySelector("strong")?.textContent === "Live",
+		);
+		await fireEvent.click(liveCard!);
+		expect(activeViewResetSpy).toHaveBeenCalledTimes(1);
+		expect(appScreenGoSpy).toHaveBeenCalledWith("game", {
+			gameId: "g-running",
+		});
 	});
 
 	test("application status badges localise pending and approved states", async () => {