FEAT: Implementation of adding friends functionality.

[SwiichyCode]

This task involves developing the feature that allows users to add friends within our application. Adding friends enables users to connect with each other, view their activities, and interact more closely within the platform.

The implementation will include creating user interface elements such as buttons or forms for adding friends, handling friend requests, and managing the friend list. Additionally, backend logic will be implemented to handle friend requests, confirmations, and updates to the user's friend list.

Users should be able to search for other users by username or email and send friend requests. Upon receiving a friend request, users should have the option to accept or reject it. Once a friend request is accepted, the users should be added to each other's friend lists, allowing them to see each other's activities and interact as friends within the application.

The implementation of adding friends enhances the social aspect of our platform and fosters stronger connections between users.