Add export plan guard to block Deye export against plan.

Force PASSIVE/no-export when sell is negative or export_mode is NONE,
and alert NEG_SELL_EXPORT in plan_actual_slot_guard when export still occurs.

Co-authored-by: Cursor <cursoragent@cursor.com>

backend/services/control/orchestrator.py

@@ -19,7 +19,11 @@ from services.control.repository import (
     _fetch_plan_row_for_slot_offset,
     _load_inverter_config,
 )
-from services.control.setpoints import _apply_price_failsafe_guard, _build_setpoints
+from services.control.setpoints import (
+    _apply_export_plan_guard,
+    _apply_price_failsafe_guard,
+    _build_setpoints,
+)
 from services.signal_service import enqueue_site_signals
 
 logger = logging.getLogger(__name__)
@@ -94,8 +98,10 @@ async def export_setpoints(site_id: int, db: asyncpg.Connection) -> None:
             )
             sp_next = sp_now
         else:
+            sp_now = _apply_export_plan_guard(site_id, mode, pi_now, sp_now)
             sp_now = _apply_price_failsafe_guard(site_id, mode, pi_now, sp_now)
             if sp_next is not None:
+                sp_next = _apply_export_plan_guard(site_id, mode, pi_next, sp_next)
                 sp_next = _apply_price_failsafe_guard(site_id, mode, pi_next, sp_next)
 
         planning_run_id = await db.fetchval(