Addresses Tobias's review concern: the generic DataIntegrityViolation
backstop turned every integrity violation into a silent 400 with no
constraint name, no stack, no Sentry — an unanticipated write bug would
fail invisibly in production.
Now extract the constraint NAME from the cause chain (schema metadata, safe
for Loki) and log it parameterized at WARN, so the failure is debuggable.
Still never pass `ex`/`getMessage()` (SQL + values, CWE-209) and still no
Sentry — the response stays generic, so the response logic is not brittle.
New test proves the WARN names the constraint but never carries the SQL.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
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