Bump README and Dockerfile to Python 3.13

[adamtheturtle]

No description provided.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 100.00%. Comparing base (147ac69) to head (5c27913).
Report is 4 commits behind head on main.

Additional details and impacted files

@@             Coverage Diff             @@
##             main     #2506      +/-   ##
===========================================
+ Coverage   99.14%   100.00%   +0.85%     
===========================================
  Files          73        73              
  Lines        5252      5252              
  Branches      190       190              
===========================================
+ Hits         5207      5252      +45     
+ Misses         43         0      -43     
+ Partials        2         0       -2     

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