fix(translate): исправление INSERT + выгрузка CSV для неуспешных запусков

**Исправления ошибок:**
- superset_executor: убран несуществующий fallback endpoint /api/v1/sql_lab/execute/
  (правильный URL /api/v1/sqllab/execute/ подтверждён браузерным запросом Superset)
  Ошибка 500 (permission denied) больше не маскируется 404
- orchestrator_run_completion: run.status=FAILED при провале insert
  (раньше всегда ставился COMPLETED). timeout тоже treated as failure
- test_orchestrator: assertion обновлён COMPLETED→FAILED

**Новая функция — выгрузка CSV:**
- GET /api/translate/runs/{run_id}/failed.csv — возвращает CSV с успешно
  переведёнными, но не вставленными записями (status=SUCCESS)
- Колонки: record_id, source_*, target_sql, source_data (JSON), языки, error_message
- Метаданные запуска (run_status, insert_status, run_error) в конце файла
- Кнопки скачивания в 3 местах фронта:
  - История запусков (при status=FAILED)
  - TranslationRunProgress (insert_failed)
  - TranslationRunResult (failed/partial/insert_failed)
- downloadFailedCsv() через fetchApiBlob + Blob URL

backend/src/api/routes/translate/_run_list_routes.py

@@ -222,4 +222,137 @@ async def download_skipped_csv(
         raise HTTPException(status_code=status.HTTP_400_BAD_REQUEST, detail=str(e))
 # #endregion download_skipped_csv
 
+
+# ============================================================
+# Download Failed CSV (uninserted records from failed runs)
+# ============================================================
+
+# #region download_failed_csv [C:4] [TYPE Function]
+# @BRIEF Download a CSV of successfully translated but uninserted records from a FAILED run.
+# @PRE User has translate.job.view permission. Run must have insert_status=failed or status=FAILED.
+# @POST Returns CSV file of records that were translated but not inserted into target DB.
+# @RATIONALE When Superset SQL Lab INSERT fails (e.g., permission denied), users need to
+#           recover the translated data. This CSV lets them manually import or retry.
+# @REJECTED Exporting ALL records from a failed run was rejected — only SUCCESS records
+#           (those with valid translations) are useful for recovery.
+
+@router.get("/runs/{run_id}/failed.csv")
+async def download_failed_csv(
+    run_id: str,
+    current_user: User = Depends(get_current_user),
+    _ = Depends(has_permission("translate.job", "VIEW")),
+    db: Session = Depends(get_db),
+):
+    """Download successfully translated but uninserted records as CSV (for failed runs)."""
+    logger.reason(f"download_failed_csv — Run: {run_id}, User: {current_user.username}",
+                  extra={"src": "translate_routes"})
+    try:
+        import csv
+        import io
+        import json
+
+        from fastapi.responses import StreamingResponse
+        from sqlalchemy.orm import joinedload
+
+        from ....models.translate import TranslationRecord, TranslationRun
+
+        run = db.query(TranslationRun).filter(TranslationRun.id == run_id).first()
+        if not run:
+            raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="Run not found")
+
+        # Export only SUCCESS records — these are the ones that were translated
+        # but could not be inserted into the target database.
+        records = (
+            db.query(TranslationRecord)
+            .options(joinedload(TranslationRecord.languages))
+            .filter(
+                TranslationRecord.run_id == run_id,
+                TranslationRecord.status == "SUCCESS",
+            )
+            .order_by(TranslationRecord.created_at)
+            .all()
+        )
+
+        if not records:
+            raise HTTPException(
+                status_code=status.HTTP_404_NOT_FOUND,
+                detail="No successful records found for this run",
+            )
+
+        # Collect all language codes across records for CSV header
+        language_codes: list[str] = []
+        seen_codes: set[str] = set()
+        for rec in records:
+            for lang in (rec.languages or []):
+                if lang.language_code and lang.language_code not in seen_codes:
+                    language_codes.append(lang.language_code)
+                    seen_codes.add(lang.language_code)
+
+        output = io.StringIO()
+        writer = csv.writer(output)
+
+        # Header: identity + source + target + per-language + metadata
+        header = [
+            "record_id", "source_object_type", "source_object_id",
+            "source_object_name", "source_sql", "target_sql",
+            "source_data",
+        ]
+        header.extend(language_codes)
+        header.append("error_message")
+        writer.writerow(header)
+
+        for rec in records:
+            # Build per-language values map
+            lang_values: dict[str, str] = {}
+            for lang in (rec.languages or []):
+                if lang.language_code:
+                    lang_values[lang.language_code] = lang.final_value or lang.translated_value or ""
+
+            # Flatten source_data JSON to string for CSV compatibility
+            source_data_str = ""
+            if rec.source_data:
+                try:
+                    source_data_str = json.dumps(rec.source_data, ensure_ascii=False)
+                except (TypeError, ValueError):
+                    source_data_str = str(rec.source_data)
+
+            row = [
+                rec.id,
+                rec.source_object_type,
+                rec.source_object_id,
+                rec.source_object_name,
+                rec.source_sql,
+                rec.target_sql,
+                source_data_str,
+            ]
+            row.extend(lang_values.get(code, "") for code in language_codes)
+            row.append(rec.error_message or "")
+            writer.writerow(row)
+
+        # Append run-level failure metadata as a comment row
+        writer.writerow([])
+        writer.writerow(["# Run failure metadata:"])
+        writer.writerow(["run_id", run.id])
+        writer.writerow(["run_status", run.status])
+        writer.writerow(["insert_status", run.insert_status or ""])
+        writer.writerow(["run_error", run.error_message or ""])
+        writer.writerow(["total_records", run.total_records or 0])
+        writer.writerow(["successful_records", run.successful_records or 0])
+
+        output.seek(0)
+        return StreamingResponse(
+            iter([output.getvalue()]),
+            media_type="text/csv",
+            headers={
+                "Content-Disposition": f"attachment; filename=failed_{run_id[:8]}.csv"
+            },
+        )
+    except HTTPException:
+        raise
+    except Exception as e:
+        logger.explore("download_failed_csv failed",
+                       extra={"src": "translate_routes", "error": str(e)})
+        raise HTTPException(status_code=status.HTTP_400_BAD_REQUEST, detail=str(e))
+# #endregion download_failed_csv
+
 # #endregion TranslateRunListRoutesModule