fix(app): demand the host directory from the workspace route (#7918)

A workspace restored at launch with no open chat had nothing demanding its host's directory on a phone, so the deck waited on hydration that never started. The workspace route now keeps its host's directory demanded while mounted, through the same hook the agent route uses.

packages/app/src/app/h/[serverId]/agent/[agentId].tsx

@@ -5,6 +5,7 @@ import { useFetchQuery } from "@/data/query";
 import { resolveAgentRoute, type AgentRouteLookup } from "@/navigation/agent-route-resolution";
 import { AgentRouteResolutionView } from "@/navigation/agent-route-resolution-view";
 import { useHasHydratedWorkspaces } from "@/stores/session-store-hooks";
+import { useDirectoryDemand } from "@/hooks/use-directory-demand";
 import { useWorkspaceLayoutStoreHydrated } from "@/stores/workspace-layout-store";
 import { useSessionStore } from "@/stores/session-store";
 import { getHostRuntimeStore, useHostRuntimeSnapshot, useHosts } from "@/runtime/host-runtime";
@@ -87,11 +88,7 @@ function HostAgentReadyRouteContent() {
   ]);
   const hasHydratedWorkspaces = useHasHydratedWorkspaces(serverId);
   const hasHydratedLayout = useWorkspaceLayoutStoreHydrated();
-  useEffect(() => {
-    if (!serverId) return;
-    // A compact app can open this route before its sidebar has demanded the directory.
-    return getHostRuntimeStore().acquireDirectoryDemand(serverId);
-  }, [serverId]);
+  useDirectoryDemand(serverId);
   const resolution = resolveAgentRoute({
     hasHydratedWorkspaces,
     hasHydratedLayout,

packages/app/src/app/h/[serverId]/workspace/[workspaceId]/index.tsx

@@ -9,6 +9,7 @@ import {
   useActiveWorkspaceSelection,
 } from "@/stores/navigation-active-workspace-store";
 import { useHasHydratedWorkspaces, useWorkspaceExists } from "@/stores/session-store-hooks";
+import { useDirectoryDemand } from "@/hooks/use-directory-demand";
 import type { WorkspaceTabTarget } from "@/workspace-tabs/model";
 import { WorkspaceScreen } from "@/screens/workspace/workspace-screen";
 import { useWorkspaceLayoutStore } from "@/stores/workspace-layout-store";
@@ -110,6 +111,10 @@ function HostWorkspaceRouteContent() {
     ? (decodeWorkspaceIdFromPathSegment(workspaceValue) ?? "")
     : "";
   const openValue = getParamValue(params.open);
+  // A restored workspace with no open chat has nothing else demanding its host's directory on a
+  // phone, where the sidebar only demands while its panel is active. Without demand the deck
+  // waits on workspace hydration that never starts.
+  useDirectoryDemand(serverId);
   useEffect(() => {
     if (!serverId || !workspaceId) {
       return;

packages/app/src/hooks/use-directory-demand.test.tsx

@@ -0,0 +1,40 @@
+/**
+ * @vitest-environment jsdom
+ */
+import { act } from "react";
+import { createRoot, type Root } from "react-dom/client";
+import { afterEach, describe, expect, it, vi } from "vitest";
+import { getHostRuntimeStore } from "@/runtime/host-runtime";
+import { useDirectoryDemand } from "./use-directory-demand";
+
+function Probe({ serverId }: { serverId: string | null }) {
+  useDirectoryDemand(serverId);
+  return null;
+}
+
+describe("useDirectoryDemand", () => {
+  let root: Root | null = null;
+  afterEach(() => {
+    act(() => root?.unmount());
+    root = null;
+    vi.restoreAllMocks();
+  });
+
+  it("demands the host directory while mounted and releases it on unmount", () => {
+    const release = vi.fn();
+    const acquire = vi
+      .spyOn(getHostRuntimeStore(), "acquireDirectoryDemand")
+      .mockImplementation(() => release);
+    const container = document.createElement("div");
+    root = createRoot(container);
+
+    act(() => root?.render(<Probe serverId="srv_a" />));
+    expect(acquire).toHaveBeenCalledTimes(1);
+    expect(acquire).toHaveBeenCalledWith("srv_a");
+    expect(release).not.toHaveBeenCalled();
+
+    act(() => root?.render(<Probe serverId={null} />));
+    expect(release).toHaveBeenCalledTimes(1);
+    expect(acquire).toHaveBeenCalledTimes(1);
+  });
+});

packages/app/src/hooks/use-directory-demand.ts

@@ -0,0 +1,16 @@
+import { useEffect } from "react";
+import { getHostRuntimeStore } from "@/runtime/host-runtime";
+
+/**
+ * Keeps a host's directory demanded while the caller is mounted.
+ *
+ * The sidebar only demands the directory while its panel is active, so a compact app that
+ * restores straight into a workspace or agent route has nothing else asking the host for
+ * workspaces and agents. Without demand the route waits on hydration that never starts.
+ */
+export function useDirectoryDemand(serverId: string | null | undefined): void {
+  useEffect(() => {
+    if (!serverId) return;
+    return getHostRuntimeStore().acquireDirectoryDemand(serverId);
+  }, [serverId]);
+}