feat: move to using pub workspaces

[eseidel]

This doesn't include ui due to: https://github.com/dart-lang/sdk/issues/60888

This won't work yet without fixing the docker files. They will need to copy the root level pubspec.lock into the docker image and then run dart pub get --offline.

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 78.10%. Comparing base (36f3cd7) to head (9eaf306).

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #107   +/-   ##
=======================================
  Coverage   78.10%   78.10%           
=======================================
  Files         193      193           
  Lines        8730     8730           
=======================================
  Hits         6819     6819           
  Misses       1911     1911           

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