Fix ESLint errors: remove unused Button import and config variable in Feed

src/components/Feed.tsx

@@ -7,11 +7,9 @@ import { NoteCard } from '@/components/NoteCard';
 import { PullToRefresh } from '@/components/PullToRefresh';
 import { FeedEmptyState } from '@/components/FeedEmptyState';
 import { Skeleton } from '@/components/ui/skeleton';
-import { Button } from '@/components/ui/button';
 import { Loader2 } from 'lucide-react';
 import LoginDialog from '@/components/auth/LoginDialog';
 import { useOnboarding } from '@/hooks/useOnboarding';
-import { useAppContext } from '@/hooks/useAppContext';
 import { useFeed } from '@/hooks/useFeed';
 import { useInfiniteHotFeed } from '@/hooks/useTrending';
 import { useCurrentUser } from '@/hooks/useCurrentUser';
@@ -54,7 +52,6 @@ interface FeedProps {
 }
 
 export function Feed({ kinds, tagFilters, header, hideCompose, emptyMessage }: FeedProps = {}) {
-  const { config } = useAppContext();
   const { user } = useCurrentUser();
   const { muteItems } = useMuteList();
   const queryClient = useQueryClient();