Display /nick and /myavatar commands according to the HS capabilities

### Your use case

#### What would you like to do?
Remove `/nick` and `/myavatar` commands when these actions are blocked server side (HS capabilities)
Even if `/myroomnick` and `/myroomavatar` don't depend on the server capabilities, it would make sense to remove them from the UI to avoid misunderstanding when the server blocks user access to PUT /_matrix/client/v3/profile/{userId}/* endpoints. They are not relevant client side in this context

#### Why would you like to do it?
Enhance the user experience

#### How would you like to achieve it?
By using the server capabilities

### Have you considered any alternatives?

_No response_

### Additional context

This request is related to https://github.com/element-hq/element-meta/issues/3167