cleanup

frontend/src/app/appState.tsx

@@ -1,5 +1,5 @@
 import React, { useContext, useEffect, useMemo, useReducer } from 'react';
-import { clearAuthToken, setAuthToken } from '../lib/apiClient';
+import { clearAuthToken, setAuthToken, setAuthRefreshHandlers } from '../lib/apiClient';
 import { ApiProvider } from './ApiContext';
 import { listTenants } from '../lib/apiClient';
 
@@ -209,6 +209,21 @@ const AppStateProvider: React.FC<{ children?: React.ReactNode }> = ({ children }
     }
   }, [state.tenant]);
 
+  useEffect(() => {
+    setAuthRefreshHandlers({
+      onRefreshSuccess: (token, payload) => {
+        dispatch({ type: 'TOKEN_REFRESH_SUCCESS', token, tenant: payload?.tenant ?? null });
+      },
+      onRefreshFailure: (error) => {
+        dispatch({ type: 'TOKEN_REFRESH_FAILURE', error: (error as Error)?.message || null });
+      },
+    });
+
+    return () => {
+      setAuthRefreshHandlers({});
+    };
+  }, [dispatch]);
+
   useEffect(() => {
     let abort = false;
 

frontend/src/app/useDocumentPreview.ts

@@ -104,7 +104,7 @@ const useDocumentPreview = ({
 
     const existing = documentLinks.get(documentId);
       const now = Date.now();
-      const expiresAt = Number.isFinite(existing?.expiresAt) ? Number(existing?.expiresAt) : null;
+      const expiresAt = existing?.expiresAt ?? null;
       if (!force && existing && (!expiresAt || expiresAt > now)) {
         return existing;
       }