fix: move network sync form population out of queryFn into useEffect

Side effects inside queryFn caused the enabled toggle and other fields to
reset on refetch because SyncStatus shares the same query key with a
different queryFn, making formLoaded unreliable.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

apps/Frontend/src/components/database-management/network-backup-manager.tsx

@@ -1,4 +1,4 @@
-import { useState } from "react";
+import { useState, useEffect } from "react";
 import { useMutation, useQuery } from "@tanstack/react-query";
 import { Button } from "@/components/ui/button";
 import { Card, CardContent, CardHeader, CardTitle } from "@/components/ui/card";
@@ -53,22 +53,24 @@ export function NetworkBackupManager() {
     },
   });
 
-  useQuery({
+  const { data: syncConfig } = useQuery({
     queryKey: ["/db/network-sync-config"],
     queryFn: async () => {
       const res = await apiRequest("GET", "/api/database-management/network-sync-config");
-      const data = await res.json();
-      if (!formLoaded) {
-        setEnabled(data.enabled ?? false);
-        setSyncHour(data.syncHour ?? 0);
-        setSourceUrl(data.sourceUrl ?? "");
-        setReceiverApiKey(data.apiKey ?? "");
-        setFormLoaded(true);
-      }
-      return data;
+      return res.json();
     },
   });
 
+  useEffect(() => {
+    if (syncConfig && !formLoaded) {
+      setEnabled(syncConfig.enabled ?? false);
+      setSyncHour(syncConfig.syncHour ?? 0);
+      setSourceUrl(syncConfig.sourceUrl ?? "");
+      setReceiverApiKey(syncConfig.apiKey ?? "");
+      setFormLoaded(true);
+    }
+  }, [syncConfig, formLoaded]);
+
   // ==============================
   // Mutations
   // ==============================