Curved arrows

[rdong8]

Please submit only one feature request in one issue!
If it is UI/UX related, don't post how a single aspect of the UI should be changed, rather in which use-case you felt
the UI is lacking or should be improved.

Is your feature request related to a problem? Please describe.
A clear and concise description of what the problem is.

I am trying to draw the self loops in a DFA:

However, we can only draw straight arrows in rnote so there is no way to make the self loops.

Describe the solution you'd like
A clear and concise description of what you want to happen.

Add cubic and quadratic bezier curve arrows .

Describe alternatives you've considered
A clear and concise description of any alternative solutions or features you've considered.

Additional context
Add any other context or screenshots about the feature request here.