Jaxparrow

- add `cyclogeostrophic_imbalance` function
- ease a posteri evaluation of the loss per grid cell

- Better handling of nan/land value 67

- fix mask init
- fully jit.able & rev-mode diff.able

- internal implementation changes in order to ease/optimize the jit operations graph generation
- add some missing docstring

- add EKE kinematic

- uses `lax.cond` and `lax.while_loop` (in place of `if/else` and `for` statements) in order to `jit` the whole cyclogeostrophy functions
- adds DUACS demo notebook