Gzip The Session JSON archive file when saving

[zmoon]

No description provided.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 89.50%. Comparing base (ba89331) to head (dafd170).
Report is 7 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main      #65      +/-   ##
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+ Coverage   89.40%   89.50%   +0.10%     
==========================================
  Files           9        9              
  Lines        1321     1334      +13     
==========================================
+ Hits         1181     1194      +13     
  Misses        140      140              

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[Copilot]

Pull Request Overview

This pull request updates the code to save and load the tune data using gzip-compressed JSON files, reducing file size and potentially improving I/O performance.

• The download functions in both files now save gzip-compressed files (with a “.gz” extension).
• The load function in pyabc2/sources/the_session.py has been updated to read from the gzipped file and now forces a re-download if the file is older than 30 days.
• Minor changes to the print statements ensure consistent output with flushing enabled.

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
pyabc2/sources/the_session.py	Updated download and load functions to handle gzip compression and add a new file age check function.
pyabc2/sources/norbeck.py	Adjusted print messages in the download workflow for consistency with progress feedback.