fix(backend): raise ItemDeletedException for soft-deleted rows across CRUD, services, and tasks

[EmanueleDeRossi1]

Purpose

Several single-item "get by ID" functions returned None for both "doesn't exist" and "soft-deleted", unlike the standard get_item_detail contract that raises ItemDeletedException (-> HTTP 410 instead of 404). Surfaced from a code comment in crud/metric.py explaining why get_metric skipped the standard pattern — turned out to be one of several.

What Changed

• crud/ layer: get_metric, get_test_set, get_test_set_by_nano_id_or_slug, get_trace_by_db_id now raise correctly; get_model deliberately kept its None-for-deleted contract (it's used elsewhere as an internal fallback resolver) but its organization filter now raises instead of silently skipping when empty; simplified several already-correct getters to call get_item_detail directly instead of duplicating its logic
• services/ and tasks/ layer: the same fix applied to EndpointService._get_endpoint, the batch execution context's endpoint and test fetches, get_test_and_prompt, all four GarakSyncService lookups, the test-set association helpers in services/test.py, get_prompts_for_test_set, all four preflight check functions, the test-generation attach-tests task, and services.test_set.get_test_set
• Fixed two exception-swallowing spots (the handle_database_exceptions decorator, handle_execution_error) that would otherwise turn the new exception into a bare 500
• Fixed a regression this same work introduced in already-shipped code: update_test_set_attributes depended on the old None-returning behavior to no-op gracefully, and would have started throwing on ordinary test updates
• Removed confirmed-dead functions found along the way: get_span_by_id, get_tool_by_provider

Testing

Added regression tests for every fixed getter; several were verified by temporarily reverting the fix and confirming the test fails first. Full backend suite passes.

[peqy]

[Improvement] Possible missing import after telemetry refactor

In apps/backend/src/rhesis/backend/app/crud/telemetry.py:get_trace_by_db_id, the function now calls UUID(trace_db_id) but the local from uuid import UUID import was removed in the diff. If UUID isn’t imported at module scope, this will raise NameError.

Fix: ensure UUID is in scope (either re-add the local import or import it at the top of the module).

Overall, the soft-delete contract unification + tests look solid.

Found 1 issue (0 critical, 1 improvement).

[peqy]

Follow-up on my prior note: crud/telemetry.py now has from uuid import UUID at module scope, so UUID(trace_db_id) in get_trace_by_db_id is in scope.

Overall the soft-delete contract unification + org scoping + count fix look solid. Ship it.

[peqy]

Confirmed the earlier concern is addressed: crud/telemetry.py has from uuid import UUID at module scope, so get_trace_by_db_id() won’t hit a NameError.

The soft-delete contract unification (raising ItemDeletedException/410) and the “don’t swallow ItemDeletedException” fixes in handle_database_exceptions + handle_execution_error look consistent. Ship it.

[peqy]

Re-checked crud/telemetry.py: UUID is imported at module scope now, so the earlier NameError concern in get_trace_by_db_id looks resolved.

No further issues spotted in the updated diff. Ship it.