Show recent sample when incidents diff is empty

handlers/system.py

@@ -438,6 +438,15 @@ async def incidents_diff(msg: Message):
 
     if not fresh:
         note = f"since {last_dt.astimezone().strftime('%Y-%m-%d %H:%M')}" if last_dt else "for the period"
+        if rows:
+            sample = rows[-50:]
+            body = "\n".join(f"{dt.astimezone().strftime('%m-%d %H:%M')}  {line}" for dt, line in sample)
+            await msg.answer(
+                f"📣 No new incidents {note} (window {hours}h).\nRecent sample:\n```\n{body}\n```",
+                reply_markup=system_logs_audit_kb,
+                parse_mode="Markdown",
+            )
+        else:
             await msg.answer(f"📣 No new incidents {note} (window {hours}h)", reply_markup=system_logs_audit_kb)
         return
     fresh.sort(key=lambda x: x[0])