Update installation instructions for uv

[namurphy]

This PR updates the installation instructions using uv to include different commands to activate virtual environments from different operating systems, since there are different commands in PowerShell and Linux/macOS.

I'll need to come back later to make sure that the group-tabs feature is working as intended.

[codecov[bot]]

Codecov Report

:white_check_mark: All modified and coverable lines are covered by tests. :white_check_mark: Project coverage is 95.50%. Comparing base (0e7e5cc) to head (588e8af). :warning: Report is 58 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #2999   +/-   ##
=======================================
  Coverage   95.50%   95.50%           
=======================================
  Files         108      108           
  Lines        9869     9869           
  Branches     1501     1501           
=======================================
  Hits         9425     9425           
  Misses        254      254           
  Partials      190      190           

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