Revise scatter register to allow custom partial bundles without scatter included by default

[archmoj]

Follow up of #5527,
Registering scatter trace outside core via lib/scatter (which used to be unused) so that one could create custom partial bundles without scatter+cartesian overhead.

cc: #5395

@plotly/plotly_js

[alexcjohnson]

Pretty cool, doesn't seem like it was that hard to make this work 😎

We'll need to do something about the default trace type - the two options that occur to me are (1) use the first trace type registered, or (2) if scatter isn't registered and you give no (valid) type, throw an error.

In addition to the bundle tests verifying behavior without scatter present, we should test components (shapes, annotations, images) and make sure something reasonable happens when the cartesian framework is missing. Perhaps that can be a silent failure, though maybe better if we could log a warning of some sort.

[nicolaskruchten]

Can we timebox this PR's remaining work to 1 hour please? This one is out of scope for the work in v2 at this point, and getting RC.1 out the door and fixing the bugs on the roadmap should take priority now :)

[archmoj]

Pretty cool, doesn't seem like it was that hard to make this work

We'll need to do something about the default trace type - the two options that occur to me are (1) use the first trace type registered, or (2) if scatter isn't registered and you give no (valid) type, throw an error.

The second option is applied in 45d3764.

[alexcjohnson]

Is it important to return true here for the no categories? In what situation would this occur?

[gvwilson]

This pull request has been sitting for a while, so I would like to close it as part of our effort to tidy up our public repositories. I've assigned it to myself to keep track of it; I'll wait until 2024-06-17 for someone to say it's still relevant and they'll to take it on, and otherwise I will close it then. Thanks - @gvwilson

[gvwilson]

@archmoj this is tied to a ticket you closed in 2021 - can we please close this PR?