Align rundown list loader with table loader

The rundown editor's list and table views render in the same container but
showed different loading states: the table now uses the shared animated
Loader while the list still showed a hardcoded "Connecting to server" ghost.
Use Loader in the list too so both view modes match.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Vq5XLTSQhU9ckZmCSW2SEr

apps/client/src/features/rundown/RundownList.tsx

@@ -1,8 +1,8 @@
 import { memo } from 'react';
 
-import Empty from '../../common/components/state/Empty';
 import { useRundownWithMetadata } from '../../common/hooks-query/useRundown';
 import { useRundownEditor } from '../../common/hooks/useSocket';
+import Loader from '../../views/common/loader/Loader';
 import Rundown from './Rundown';
 
 export default memo(RundownList);
@@ -13,7 +13,7 @@ function RundownList() {
   const isLoading = status !== 'success' || !data || !rundownMetadata;
 
   if (isLoading) {
-    return <Empty text='Connecting to server' />;
+    return <Loader />;
   }
 
   return (