Restore an archived workspace when its agent is reopened

Reopening an archived agent previously dead-ended at "workspace not
found": the agent record was un-archived but its workspace stayed
archived and was never sent to the client.

The daemon now un-archives the owning workspace alongside the agent when
its backing directory still exists, and the app auto-fires the restore
ahead of the missing-workspace gate so the user lands back in the
workspace rather than a dead end.

Worktrees whose directory was deleted on archive are not yet restorable
(recreating them from their branch is a follow-up); the workspace record
now persists its base branch as groundwork for that.

packages/app/src/screens/workspace/workspace-screen.tsx

@@ -71,7 +71,11 @@ import { useToast } from "@/contexts/toast-context";
 import { useExplorerOpenGesture } from "@/hooks/use-explorer-open-gesture";
 import { selectIsFileExplorerOpen, usePanelStore } from "@/stores/panel-store";
 import { type ExplorerCheckoutContext } from "@/stores/explorer-checkout-context";
-import { useSessionStore, type WorkspaceDescriptor } from "@/stores/session-store";
+import {
+  useSessionStore,
+  useWorkspaceRestoreStatus,
+  type WorkspaceDescriptor,
+} from "@/stores/session-store";
 import {
   buildWorkspaceTabPersistenceKey,
   collectAllTabs,
@@ -1487,6 +1491,7 @@ function useWorkspaceRouteActions(normalizedServerId: string): {
 
 function useResolvedWorkspaceRouteState(input: {
   serverId: string;
+  workspaceId: string;
   workspace: WorkspaceDescriptor | null;
   hasHydratedWorkspaces: boolean;
 }): WorkspaceRouteState {
@@ -1497,6 +1502,7 @@ function useResolvedWorkspaceRouteState(input: {
   );
   const hostSnapshot = useHostRuntimeSnapshot(input.serverId);
   const hostName = useMemo(() => getHostDisplayName(host, input.serverId), [host, input.serverId]);
+  const restoreStatus = useWorkspaceRestoreStatus(input.serverId, input.workspaceId);
 
   return useMemo(
     () =>
@@ -1506,6 +1512,7 @@ function useResolvedWorkspaceRouteState(input: {
         lastError: hostSnapshot?.lastError ?? null,
         workspace: input.workspace,
         hasHydratedWorkspaces: input.hasHydratedWorkspaces,
+        restoreStatus,
       }),
     [
       hostName,
@@ -1513,6 +1520,7 @@ function useResolvedWorkspaceRouteState(input: {
       hostSnapshot?.lastError,
       input.workspace,
       input.hasHydratedWorkspaces,
+      restoreStatus,
     ],
   );
 }
@@ -1858,6 +1866,7 @@ function WorkspaceScreenContent({
   );
   const workspaceRouteState = useResolvedWorkspaceRouteState({
     serverId: normalizedServerId,
+    workspaceId: normalizedWorkspaceId,
     workspace: workspaceDescriptor,
     hasHydratedWorkspaces,
   });