fix(scada): verify first sample after field completion

app/infra/db/timescaledb/repositories/scada.py

@@ -1,5 +1,5 @@
 from typing import List, Any
-from datetime import datetime
+from datetime import datetime, timedelta
 from collections import defaultdict
 from psycopg import AsyncConnection, Connection, sql
 from psycopg.rows import dict_row
@@ -131,6 +131,29 @@ class ScadaRepository:
             )
             return await cur.fetchall()
 
+    @staticmethod
+    async def get_recovery_scada_readings(
+        conn: AsyncConnection, device_ids: list[str], incident_at: datetime,
+        returned_at: datetime, through: datetime, *, baseline_limit: int = 100_001,
+    ) -> list[dict]:
+        """Read the causal reference and exactly the first stored frame after T."""
+        if not device_ids or through <= returned_at:
+            return []
+        async with conn.cursor() as cur:
+            await cur.execute(
+                "WITH next_frame AS (SELECT min(time) AS time FROM scada.measurements "
+                "WHERE device_id=ANY(%s) AND time>%s AND time<=%s), "
+                "reference AS (SELECT time,device_id,monitored_value,cleaned_value "
+                "FROM scada.measurements WHERE device_id=ANY(%s) AND time>=%s AND time<%s "
+                "ORDER BY time,device_id LIMIT %s) "
+                "SELECT time,device_id,monitored_value,cleaned_value FROM reference UNION ALL "
+                "SELECT m.time,m.device_id,m.monitored_value,m.cleaned_value FROM scada.measurements m "
+                "JOIN next_frame f ON m.time=f.time WHERE m.device_id=ANY(%s) ORDER BY time,device_id",
+                (device_ids, returned_at, through, device_ids, incident_at - timedelta(days=15),
+                 incident_at, baseline_limit, device_ids),
+            )
+            return [dict(row) for row in await cur.fetchall()]
+
     @staticmethod
     async def get_latest_scada_readings(
         conn: AsyncConnection,