chore: add trigger to abort checkpoint deletion

[amandavialva01]

Description

Adds a trigger that avoids deleting checkpoints from the database if they aren't marked as DELETED, indicating their deletion from storage.

Test Plan

CI passes.

Commentary (optional)

Checklist

• Changes have been manually QA'd
• User-facing API changes need the "User-facing API Change" label.
• Release notes should be added as a separate file under docs/release-notes/.
  See Release Note for details.
• Licenses should be included for new code which was copied and/or modified from any external code.

Ticket

DET-10027

[netlify]

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 47.55%. Comparing base (c029327) to head (de80b45).
Report is 13 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #8878   +/-   ##
=======================================
  Coverage   47.54%   47.55%           
=======================================
  Files        1065     1065           
  Lines      170218   170218           
  Branches     2241     2241           
=======================================
+ Hits        80937    80940    +3     
+ Misses      89123    89120    -3     
  Partials      158      158           

Flag	Coverage Δ
backend	43.35% <ø> (ø)
harness	63.82% <ø> (+<0.01%)	⬆️
web	42.53% <ø> (ø)

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see 3 files with indirect coverage changes

[jesse-amano-hpe]

Looks good to me!