Only serialize ESM model definition if session is already loaded

[philippjfr]

The fix introduced in #8432 caused a regression because it was not correctly scoped. Specifically we should only serialize model definitions if the session is already fully initialized. This change adds an additional condition using state.loaded to ensure that is the case.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 85.50%. Comparing base (8644d22) to head (abc0d38).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@             Coverage Diff             @@
##             main    #8462       +/-   ##
===========================================
+ Coverage   70.36%   85.50%   +15.13%     
===========================================
  Files         348      349        +1     
  Lines       55025    55026        +1     
===========================================
+ Hits        38719    47050     +8331     
+ Misses      16306     7976     -8330     

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[github-actions]

This pull request has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.