Support source as an input value type #241

I have a strategy builder that takes in multiple different inputs as a source from other indicators and executes actions according to the conditions.

In order to test this indicator it would require passing other indicator output references as an input value but currently, these are the supported input types:

const types = {
  bool: 'Boolean',
  integer: 'Number',
  float: 'Number',
  text: 'String',
};

Also, the study holds only one indicator instance so it loses reference when the new indicator is added.

So for all this to work the study would need to handle and track multiple indicators and set PineIndicator inputs as a source from a different indicator.

While debugging TV ws messages I noticed that it sends input.source value as an indicator id in the study with the output id prefix like st4$4 where st4 is id and $4 is an output id prefix.

Is that something that would be possible to implement?
That would be a game changer!