EKF2/EKF3: always push data to EKF instead of having EKF sometimes pull from sensor

In EKF2/3 we sometimes push data into the EKF (for example we push external position estimates into the EKF) but other times the EKF pulls data directly from the sensor (i.e. rangefinder?).

We should consolidate the interface so that the vehicle code (or perhaps sensor itself) is always pushing data into the EKF.

The benefits of doing this are:

- more consistent interface
- allows replay to work better?

I'm creating this issue because I've heard @priseborough mention this a couple of times.

Read the EKF2/EKF3 sensor interfaces and vehicle-side sensor update paths first; compare data that is pushed with data pulled directly from sensors. Completion means relevant sensor inputs use one consistent direction and replay behavior is improved, but the issue names no files or tests.

Written by the indexing model from the issue text.