feat(lib): add basic vertex diffraction

[jeertmans]

No description provided.

[github-actions]

Benchmark results:

Benchmark	before	changes
accumulate_on_transmitters_grid_over_paths_noapprox	33.0 ms	32.6 ms: 1.01x faster
path_method_image	42.2 us	42.5 us: 1.01x slower
path_method_FPT	77.0 us	77.6 us: 1.01x slower
Geometric mean	(ref)	1.00x faster

Benchmark hidden because not significant (2): accumulate_on_transmitters_grid_over_paths_approx, path_method_MPT

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 100.00%. Comparing base (ab6f9fb) to head (3c54745).
Report is 19 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff            @@
##              main       #70   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files            9         9           
  Lines          928       976   +48     
=========================================
+ Hits           928       976   +48     

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