Keep slash commands visible after New Workspace (#1760)

* fix(app): keep slash commands visible after New Workspace

Repeated returns from the app-wide New Workspace route were using dismissTo with the workspace leaf URL. That updated the root URL without popping the nested host stack, so hidden duplicate workspace deck entries could remain mounted and steal composer popover measurements.

Dispatch a root-stack POP_TO into the host workspace route instead, with a Playwright regression for the slash-command popover.

* test(app): tighten workspace autocomplete regression

Derive the expected deck count from the seeded workspaces and make the duplicate-deck assertion hard. Keep the Expo Router pop hint documented because removing it reproduces the hidden deck entries.

packages/app/e2e/composer-autocomplete.spec.ts

@@ -1,8 +1,14 @@
 import { expect, test, type Page } from "./fixtures";
 import { composerLocator, expectComposerVisible } from "./helpers/composer";
-import { openAgentRoute, seedMockAgentWorkspace } from "./helpers/mock-agent";
+import {
+  openAgentRoute,
+  seedMockAgentWorkspace,
+  type MockAgentWorkspace,
+} from "./helpers/mock-agent";
 import { expectWorkspaceTabVisible } from "./helpers/archive-tab";
 import { daemonWsRoutePattern } from "./helpers/daemon-port";
+import { getServerId } from "./helpers/server-id";
+import { switchWorkspaceViaSidebar } from "./helpers/workspace-ui";
 
 const TEST_COMMANDS = [
   {
@@ -142,6 +148,43 @@ async function installListCommandsStub(page: Page): Promise<void> {
   });
 }
 
+async function openAppWideNewWorkspace(page: Page): Promise<void> {
+  await page.getByTestId("sidebar-global-new-workspace").first().click();
+  await page.waitForURL((url) => url.pathname === "/new", { timeout: 30_000 });
+}
+
+async function expectSingleCurrentWorkspaceDeckEntry(
+  page: Page,
+  input: { expectedDeckEntryCount: number; serverId: string; workspaceId: string },
+): Promise<void> {
+  const summary = await page
+    .locator('[data-testid^="workspace-deck-entry-"]')
+    .evaluateAll((elements, target) => {
+      const currentTestId = `workspace-deck-entry-${target.serverId}:${target.workspaceId}`;
+      const entries = elements.map((element) => {
+        const rect = element.getBoundingClientRect();
+        return {
+          testId: element.getAttribute("data-testid"),
+          hasLayout: rect.width > 0 && rect.height > 0,
+        };
+      });
+      const currentEntries = entries.filter((entry) => entry.testId === currentTestId);
+      return {
+        totalDeckEntryCount: entries.length,
+        currentWorkspaceEntryCount: currentEntries.length,
+        visibleCurrentWorkspaceEntryCount: currentEntries.filter((entry) => entry.hasLayout).length,
+        hiddenCurrentWorkspaceEntryCount: currentEntries.filter((entry) => !entry.hasLayout).length,
+      };
+    }, input);
+
+  expect(summary).toEqual({
+    totalDeckEntryCount: input.expectedDeckEntryCount,
+    currentWorkspaceEntryCount: 1,
+    visibleCurrentWorkspaceEntryCount: 1,
+    hiddenCurrentWorkspaceEntryCount: 0,
+  });
+}
+
 async function openReadyMockAgent(
   page: Page,
   options?: { expectWorkspaceTab?: boolean },
@@ -308,6 +351,64 @@ function expectPopoverDoesNotDisappearAfterFirstVisible(frames: PopoverFrame[]):
 }
 
 test.describe("Composer autocomplete", () => {
+  test("stays visible after returning from the app-wide new workspace route", async ({ page }) => {
+    await installListCommandsStub(page);
+    const serverId = getServerId();
+    const sessions: MockAgentWorkspace[] = [];
+
+    try {
+      sessions.push(
+        await seedMockAgentWorkspace({
+          repoPrefix: "autocomplete-new-route-a-",
+          title: "Autocomplete new route A",
+        }),
+      );
+      sessions.push(
+        await seedMockAgentWorkspace({
+          repoPrefix: "autocomplete-new-route-b-",
+          title: "Autocomplete new route B",
+        }),
+      );
+      sessions.push(
+        await seedMockAgentWorkspace({
+          repoPrefix: "autocomplete-new-route-c-",
+          title: "Autocomplete new route C",
+        }),
+      );
+
+      const [first, second, third] = sessions;
+
+      await openAgentRoute(page, first);
+      await expectComposerVisible(page, { timeout: 30_000 });
+
+      await openAppWideNewWorkspace(page);
+      await switchWorkspaceViaSidebar({ page, serverId, workspaceId: second.workspaceId });
+      await expectComposerVisible(page, { timeout: 30_000 });
+
+      await openAppWideNewWorkspace(page);
+      await switchWorkspaceViaSidebar({ page, serverId, workspaceId: third.workspaceId });
+      await expectComposerVisible(page, { timeout: 30_000 });
+
+      await openAppWideNewWorkspace(page);
+      await switchWorkspaceViaSidebar({ page, serverId, workspaceId: first.workspaceId });
+      await expectComposerVisible(page, { timeout: 30_000 });
+      await expectSingleCurrentWorkspaceDeckEntry(page, {
+        expectedDeckEntryCount: sessions.length,
+        serverId,
+        workspaceId: first.workspaceId,
+      });
+
+      await composerLocator(page).fill("/");
+      const popover = page
+        .getByTestId("composer-autocomplete-popover")
+        .filter({ hasText: "/help", visible: true })
+        .first();
+      await expect(popover).toBeInViewport({ timeout: 30_000 });
+    } finally {
+      await Promise.allSettled(sessions.map((session) => session.cleanup()));
+    }
+  });
+
   test("does not flash at the wrong position on the first slash command paint", async ({
     page,
   }) => {