class CreateCustom

Creates a Custom node with the given options.

Custom nodes apply custom effects to one or more source streams,

producing one or more destination streams. The effects are implemented

out-of-process via a call to a FIDL interface.

Custom nodes are composite nodes that encapsulate a fixed number of

sources and destinations. We assign an ID to each of these source and

destination slots -- see [`CustomNodeProperties`]. This allows creating

edges that target a specific slot. For example, a node that implements

AEC will have loopback and microphone source slots and the caller will

need to connect each source slot to an appropriate source. The caller

can do this by calling `CreateEdge` using a specific [`NodeId`] from

[`CustomNodeProperties.source_ids`]. These internal IDs cannot be

deleted, except by deleting the entire Custom node.

The returned `id` describes the composite node. Passing `id` to

[`DeleteNode`] will delete the composite node as well as any internal

source and destination nodes. The returned `id` cannot be used in

[`CreateEdge`]. Edges must target a specific source or destination slot

as described above.