class Server

Returns a list of available camera IDs when it has changed from the previously returned

list of IDs, or when it is called by a client for the first time. The returned list may be

empty, indicating no cameras are available. The IDs returned to the client will remain

consistent with respect to the physical devices they represent for the duration of the

client's connection. Events will be sorted first by event type - `existing`, `added`,

`removed`. Within each event type range, IDs will be provided in ascending order. Events

are coalesced by the server, so a given ID will only appear once in each list of events.

Please note that it is entirely possible for the list returned to be temporarily empty even

if the local camera hardware is hardwired (vs plug-in like USB). The empty list condition

is temporary on such a platform.

Camera applications should tolerate an empty list returned, and attempt to retry the

`WatchDevices()` call.

Acquires a camera interface for the given ID. If any clients already exist for this camera,

the request is closed with the ZX_ERR_ALREADY_BOUND epitaph.

|bind_handler| returns a handler that binds incoming connections to this

server implementation.

The returned handler borrows the server instance.

The server must outlive the provided |dispatcher|. Only after

the dispatcher is shutdown will it be safe to destroy the servers.

The server should not be moved.