notes on plans with the rest of dimension classes

[martinfleis]

This is more a discussion than actual PR. I went through dimension.py and thought about the future of all of the classes we have there. There are two main questions

1. Do we keep these as thin wrappers around Graph.lag or point directly to lag?
2. What should be moved to libpysal and how?

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 97.7%. Comparing base (29c0e5d) to head (b38fa2e).
Report is 19 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##            main    #536     +/-   ##
=======================================
+ Coverage   97.5%   97.7%   +0.2%     
=======================================
  Files         26      32      +6     
  Lines       4189    4996    +807     
=======================================
+ Hits        4086    4882    +796     
- Misses       103     114     +11     

Files	Coverage Δ
momepy/dimension.py	98.7% <ø> (ø)

... and 17 files with indirect coverage changes

[martinfleis]

I am going to merge this to keep the notes in sync with the development