Limit python and JAX versions

Add charge so fadge can handle the Kerr-Newman spacetime; update GitHub actions and dependencies.

Add position angle to command line argument

Add position angle to command line argument.

Include coordinate time; improve default values

Include coordinate time; improve default values.

Match XAJ option name; use `hlower`

Match XAJ option name; use hlower.

Support offsets

Adjust default values; support offsets.

Move `PRay`'s geodesic integration function to `fadge`

Move PRay's geodesic integration function to fadge because geodesic integration is purely geometrical.

Improve dependency

Pin the xaj versions.

First release of fadge

Fast automatic differential geometry with JAX.