Make Kernels a compile time constant

[Benny-Nottonson]

Is your feature request related to a problem? Please describe.
I believe this issue is impossible to do without hashmaps, but I could be wrong. Currently Kernels are instantiated for every graph that is made, though they are really just a psuedo hashmap that could be a compile time constant.

Describe the solution you'd like
Rewrite graph and node to use a hash map version of kernels once mojo supports it.

Describe alternatives you've considered
The current implementation works but likely comes with some performance overhead.