Function prepareForListeningWithContextualDecodingGraph

prepareForListeningWithContextualDecodingGraph(
    dgName: string,
    contextId: number,
    computeGoP?: boolean,
): Promise<boolean>
Prepare the recognizer to listen using a contextual decoding graph at a specific context index.

Call this to switch between contexts without rebuilding the graph. The recognizer will only match phrases from the selected context.
Parameters
- dgName: string
  Name of the contextual decoding graph (created via createContextualDecodingGraphFromPhrases).
- contextId: number
  Zero-based index of the context to activate.
- computeGoP: boolean = false
  If true, compute GoP scores. Defaults to false.
Returns Promise<boolean>
true if preparation succeeded, false if the context index is out of bounds or the graph doesn't exist.