Grid and domain cleanup/documentation

[skygering]

I cleaned up the gird and domain code and added more documentation for the website.

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 74.77064% with 55 lines in your changes missing coverage. Please review.

Project coverage is 80.76%. Comparing base (285032b) to head (f97d9f5).

Files	Patch %	Lines
...ulation_components/domain_components/boundaries.jl	77.22%	23 Missing ⚠️
...simulation_components/domain_components/domains.jl	71.42%	10 Missing ⚠️
src/simulation_components/grids.jl	73.68%	10 Missing ⚠️
...ulation_components/domain_components/topography.jl	74.07%	7 Missing ⚠️
...n_components/domain_components/abstract_domains.jl	0.00%	5 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #110      +/-   ##
==========================================
- Coverage   81.94%   80.76%   -1.18%     
==========================================
  Files          24       28       +4     
  Lines        2720     2782      +62     
==========================================
+ Hits         2229     2247      +18     
- Misses        491      535      +44     

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