Car docs: add auto-resume column

[sshane]

Need it in car interface (and not car info), because it's conditional on openpilot long control and whether we can spam the buttons

Preview: https://github.com/commaai/openpilot/blob/auto-resume-car-info/docs/CARS.md

[sshane]

@adeebshihadeh anything else you want to show?

[jyoung8607]

To follow up on my DM conversation with @sshane, I think VW's auto resume can be mostly described by minEnableSpeed == -1. We also have a case of not supporting SnG with manual transmissions, but technically it's a bug that we don't encode a minEnableSpeed for those cars with stock ACC (it's in the openpilot long draft PR) so we should just fix that bug instead.

The sticky part is describing FtS cars, the cars that will stop but not stay stopped. I don't quite know how to identify model-year combinations with that problem yet. I propose we use the column-specific footnote capability to add a footnote in the new resume-from-stop column saying "provided the car has an electric parking brake", and a similar exception for the comma.ai/vehicles doc generator. I believe that makes an accurate statement, or at least more accurate than we make today.

[jyoung8607]

On further thought, we'll have to mention manual transmissions in the footnote/caveat. We live-identify those carParams within a model rather than making separate models, any supported VW could theoretically have a manual transmission, and the docs will have to reflect that.

[sshane]

@jyoung8607 want to open that PR to add the footnote to see how it looks?