Disable setting/clearing status when no connectivity

When you're trying to set or clear your status when having no connectivity, it just silently fails (e.g. as if nothing happened).

Since web platform does not currently have one consistent way to address such situations (in some cases an error modal is shown, in other cases there's a red text under the specific field), we apply the minimum of disabling the related controls when we have determined that there's no connectivity. Do determine if there's connectivity we use the existing mechanism that also triggers the current banner at the top of the room's composer.

Locate the web code that sets or clears the user status and compare it with the mobile platform's behavior. Verify that a spinner remains visible while the network request is pending and that a small error toast appears when the request fails, including when there is no connectivity.

Written by the indexing model from the issue text.