fix: improve cross-device evidence, request diagnostics and prompt efficiency

artemis/data_engine/storage.py

@@ -990,6 +990,9 @@ class StorageManager:
                         WHEN excluded.status = 'running' AND traces.status IN ('success', 'failed') THEN traces.payload
                         ELSE excluded.payload
                     END
+                WHERE traces.type != 'llm_diagnostic'
+                   OR COALESCE(json_extract(excluded.payload, '$.sequence'), 0)
+                      > COALESCE(json_extract(traces.payload, '$.sequence'), -1)
                 """,
                 (
                     str(trace.trace_id),