Implement WebSocket provider for real-time post updates; add Ctrl+Ent…

[L4B0MB4]

This pull request includes several changes to improve the post creation and listing functionality, as well as the integration of WebSocket for real-time updates. The most important changes are summarized below:

Real-time Updates Integration:

• frontend/src/pages/main.tsx: Added WebsocketProvider to enable WebSocket connections for real-time updates.
• frontend/src/websocket/websocketProvider.tsx: Implemented WebsocketProvider to handle WebSocket connections and dispatch new posts using addPostSync.

Post Creation and Listing Enhancements:

• frontend/src/components/posts/createpost.tsx: Added onKeyUp event to trigger onUpload when Ctrl+Enter is pressed, improving user experience.
• frontend/src/components/posts/postlist.tsx: Removed the useInterval hook to stop fetching posts every second, optimizing performance. [1] [2]
• frontend/src/statemanagement/posting/postSlice.ts: Refactored usersSlice to postSlice and added addPostSync reducer to handle synchronous post additions. [1] [2]

Code Cleanup:

• frontend/src/hooks/useInterval.ts: Removed the useInterval hook as it is no longer needed.