fix(backup): harden postgres dump job error handling

[vcnainala]

Summary

• Improve DataBackupJob failure reporting and backup workflow robustness.
• Align unit tests with the revised job behavior.

Test plan

• php artisan test tests/Unit/Jobs/DataBackupJobTest.php
• Trigger backup on staging and verify success/failure visibility in logs.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 75.46%. Comparing base (69edb6c) to head (026f60a).
⚠️ Report is 87 commits behind head on development.

Additional details and impacted files

@@                Coverage Diff                 @@
##             development    #1420       +/-   ##
==================================================
+ Coverage          56.63%   75.46%   +18.83%     
- Complexity          2268     3328     +1060     
==================================================
  Files                207      234       +27     
  Lines               8733    12485     +3752     
==================================================
+ Hits                4946     9422     +4476     
+ Misses              3787     3063      -724     

Flag	Coverage Δ
unittests	75.46% <100.00%> (+18.83%)	⬆️

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