Make sure model is always inspectable at console!

Perhaps there should be a test for this so we don't accidentally find ourselves inspecting an issue in production release with no (easy) way to get access to the model object from the console.
add sampleBatchLength property to signal generator

IS [#63728770]

This stores samples in a 'batch' of length sampleBatchSize, deferring all tick events until the batch is full. When the batch is full, it synchronously issues one tick per sample in the batch until the batch is emptied.

This will allow us to test the possible behavior of the LabQuest2 sensor model (which has to deal with receiving batches of samples from the LabQuest2) under the assumption that we maintain the "one tick per sample" assumption of the other models.
Batched signal generator interactive

IS [#63728770]

This is useful for testing how well the Lab grapher deals with receiving many synchronous ticks, each with a new sample. The first version of the LabQuest2 sensor model may receive batches of ~60 samples at a time, but the current architecture dictates that we issue on tick event for each sample (thus, 60 sequential tick events and 60 sequential draws). The dataset-based architecture which might avoid this issue is not quite ready yet.