Numba backend cached property refactor (tests may compile slower since JIT cache is now local to backend instance)

[slayoo]

No description provided.

[codecov]

Codecov Report

Attention: Patch coverage is 86.71756% with 87 lines in your changes are missing coverage. Please review.

Project coverage is 83.64%. Comparing base (c2b4850) to head (29b4dfd).
Report is 2 commits behind head on main.

Files	Patch %	Lines
...ckends/impl_numba/methods/fragmentation_methods.py	66.34%	70 Missing ⚠️
PySDM/backends/impl_numba/methods/pair_methods.py	89.13%	10 Missing ⚠️
...SDM/backends/impl_numba/methods/moments_methods.py	91.66%	3 Missing ⚠️
.../backends/impl_numba/methods/collisions_methods.py	98.54%	2 Missing ⚠️
...ackends/impl_numba/methods/displacement_methods.py	92.85%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1299      +/-   ##
==========================================
+ Coverage   83.47%   83.64%   +0.16%     
==========================================
  Files         362      364       +2     
  Lines        8868     8932      +64     
==========================================
+ Hits         7403     7471      +68     
+ Misses       1465     1461       -4     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.