Task 627: DuckDB Explorer Query Result Validation E2E Tests

Status: DONE

Problem

The data explorer E2E tests only verify that DuckDB initializes and that clicking a preset makes the result table visible. No test checks that queries actually return correct data — a broken data ingestion or schema change would go undetected.

Solution

Add E2E tests that:

1. Execute a preset query and verify results contain expected data (non-empty rows, expected columns)
2. Execute a custom SQL query and verify result correctness
3. Test error handling for malformed SQL

Files to Modify

• ts/e2e/reports.spec.ts — Add DuckDB query validation tests