Preserve max moment of control key while appending to circuit

[p51lee]

Control operations sharing the same control key could be assigned an earlier moment index, causing later measurements to appear before earlier controls.

This change updates ckey_indices to keep the maximum moment index seen so far, preventing reordering of classical controls and measurements.

Fixes #7622, fixes #7623

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 99.56%. Comparing base (c334f75) to head (02ce65c).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #7626      +/-   ##
==========================================
- Coverage   99.56%   99.56%   -0.01%     
==========================================
  Files        1088     1088              
  Lines       96039    96048       +9     
==========================================
+ Hits        95623    95631       +8     
- Misses        416      417       +1     

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

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

[daxfohl]

lgtm. thanks for including the code comments!

[pavoljuhas]

Thank you for reporting and fixing!

PS: I have tweaked the test to compare with the expected circuit.