New Chart won't aggregate data

### Background
In this release announcement @djpirl demos the new chart component automatically aggregating data, using a accidents data value from a Text basic column. However, I have found that in attempting to do the same thing, I am not able to aggregate any text from either Glide Tables or Glide Big Table sources, at least not in the Y axis.

### Problem
I have a table of leads, their Lead Source (how did you hear about us?) is populated via a form into a basic text column. The date the lead was added to the table is stored in a Date Added date and time column. Using the date and time column as the X axis, and choosing the lead source column as the Y axis, I just get counts of values, nothing aggregated.

However, if I use the lead source as the X axis, and the name (for testing purposes) as the Y axis, the chart component automatically aggregates the data on the X axis for me by showing a breakdown:

### Use Case
This limitation makes it very difficult to display values over time easily for a user who wants to understand the source of their leads generated, for instance if they run an ad campaign one month and want to know if it was effective for the lead source where the ad was placed.

I'd love it if the aggregation of data worked for both X and Y axes, so that the chart can be extended to use for common reporting use cases. For this case, I have to build complex helper tables to query for specific values rather than allowing them to be dynamic (lead sources could be anything in their form). My expectation would be that the chart component can split values into different bars to show the different values from the text column as it does on the X axis in the above example.

An example goal chart would be something like this: