Provide mechanism for waiting to be able to perform presence operations

[lawrence-forooghian]

That is, to be able to implement the following:

** @(CHA-PR3d)@ @[Testable]@ If the room status is @Attaching@, then the @enter@ call will wait for the attach operation to succeed and then call the underlying presence @enter@ operation. It will throw an error if the attach fails.
** @(CHA-PR3e)@ @[Testable]@ If the room status is @Attached@, then the @enter@ call will invoke the underlying @presence.enter()@ call.
** @(CHA-PR3f)@ @[Testable]@ If the room status is @Detached@, an @ErrorInfo@ with code 40000, explaining that attach must be called first, will be thrown.
** @(CHA-PR3g)@ @[Testable]@ For any other room status, an @ErrorInfo@ with code 40000 will be thrown.

and the equivalent in:

• CHA-PR10d - g
• CHA-PR6c - f
• CHA-T2c - f

┆Issue is synchronized with this Jira Task by Unito