[Feat] Add the option to make channels role-specific

[abi-sheks]

Is your feature request related to a problem? Please describe.
Currently, all channels within a server are accessible to any user with appropriate permissions, but there is no way to limit channel access to specific roles. This can lead to cluttered channels where not all users should be interacting.

Describe the solution you'd like
Introduce an option to make channels role-specific, so that only users with certain roles can access and send messages to a channel. This functionality should:

• Change the channel schema to include roles as well
• Allow the server owner or moderator to assign a specific role to a channel, determining which roles are allowed to access the channel.
• Provide a command like set-channel-role <channel_name> <role_name> to set which roles can access a specific channel.