Standardise frontend hook fetch error handling and mark Task 12 done

frontend/src/hooks/useServerStatus.ts

@@ -8,6 +8,7 @@
 
 import { useCallback, useEffect, useRef, useState } from "react";
 import { fetchServerStatus } from "../api/dashboard";
+import { handleFetchError } from "../utils/fetchError";
 import type { ServerStatus } from "../types/server";
 
 /** How often to poll the status endpoint (milliseconds). */
@@ -49,7 +50,7 @@ export function useServerStatus(): UseServerStatusResult {
       setBanguiVersion(data.bangui_version);
       setError(null);
     } catch (err: unknown) {
-      setError(err instanceof Error ? err.message : "Failed to fetch server status");
+      handleFetchError(err, setError, "Failed to fetch server status");
     } finally {
       setLoading(false);
     }