refactor(30-01): wrap JKSessionRemoteTracks with React.memo

- Add memo to React imports (with useMemo)
- Wrap component with memo(function JKSessionRemoteTracks)
- Add displayName for React DevTools
- Prevents unnecessary re-renders when mixerHelper and sessionModel props unchanged

jam-ui/src/components/client/JKSessionRemoteTracks.js

@@ -1,11 +1,11 @@
-import React, { useMemo } from 'react';
+import React, { useMemo, memo } from 'react';
 import { useSelector } from 'react-redux';
 import { selectActiveSession } from '../../store/features/activeSessionSlice';
 import { useAuth } from '../../context/UserAuth';
 import JKSessionAudioInputs from './JKSessionAudioInputs';
 import { getAvatarUrl, getInstrumentIcon45_inverted } from '../../helpers/utils';
 
-const JKSessionRemoteTracks = ({ mixerHelper, sessionModel }) => {
+const JKSessionRemoteTracks = memo(function JKSessionRemoteTracks({ mixerHelper, sessionModel }) {
   // Phase 4: Replace CurrentSessionContext with Redux
   const currentSession = useSelector(selectActiveSession);
   const { currentUser } = useAuth();
@@ -74,6 +74,8 @@ const JKSessionRemoteTracks = ({ mixerHelper, sessionModel }) => {
       ))}
     </div>
   );
-};
+});
+
+JKSessionRemoteTracks.displayName = 'JKSessionRemoteTracks';
 
 export default JKSessionRemoteTracks;