refactor: show correct values for min/max labels when plotting a field

[moe-ad]

For a field having a dimensionality > 1 e.g. a displacement field, the min_max operator determines the max/min value of that field based on the norm of each entry. This means we should label the location where these values occur correspondingly.

Before:

After:

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 84.41%. Comparing base (3c88854) to head (a1f4af6).
⚠️ Report is 1 commits behind head on main.
✅ All tests successful. No failed tests found.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2883      +/-   ##
==========================================
+ Coverage   84.38%   84.41%   +0.02%     
==========================================
  Files          92       92              
  Lines       10937    10937              
==========================================
+ Hits         9229     9232       +3     
+ Misses       1708     1705       -3