feat: Implement core chat page with channel navigation, direct messages, and voice chat integration.

Frontend/Electron/src/pages/Chat.jsx

@@ -43,6 +43,7 @@ const Chat = () => {
     }, [toggleMute]);
 
     const channels = useQuery(api.channels.list) || [];
+    const categories = useQuery(api.categories.list) || [];
 
     const rawChannelKeys = useQuery(
         api.channelKeys.getKeysForUser,
@@ -246,6 +247,7 @@ const Chat = () => {
             <div className="app-container">
                 <Sidebar
                     channels={channels}
+                    categories={categories}
                     activeChannel={activeChannel}
                     onSelectChannel={handleSelectChannel}
                     username={username}