fix(gateway): detect coordinator staging before charge ownership checks

A coordinator whose charge end entity was not (yet) owned by the gateway
was refused with an ownership error, so its charge window was never
written, instead of keeping its staged separate-endpoint sequence.
Identify coordinators first, as that decision only needs the entity names
and discovery record. Same ordering as the discharge side in #5532.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

Author: CI

apps/predbat/inverter.py

@@ -3638,13 +3638,13 @@ def write_and_poll_gateway_charge_window(self, new_start, new_end):
         gateway = components.get_component("gateway") if components else None
         names = ("charge_start_time", "charge_end_time")
         target = (new_start, new_end)
+        if gateway is not None and gateway.charge_window_uses_staging(*entities):
+            return None  # Coordinator slot staging must precede its enable write.
         if owners != ["gateway", "gateway"] or gateway is None:
             self.base.record_status(f"Warn: Inverter {self.id} Hub charge window has inconsistent entity ownership", had_errors=True)
             return False
         if not all(self.check_write_entity("write_and_poll_gateway_charge_window", name, entity, value) for name, entity, value in zip(names, entities, target)):
             return False
-        if gateway.charge_window_uses_staging(*entities):
-            return None  # Coordinator slot staging must precede its enable write.
 
         def read_pair():
             """Read both endpoint entities without substituting desired values."""

apps/predbat/tests/test_gateway_charge_window.py

@@ -203,6 +203,19 @@ def test_coordinator_slot_staging_keeps_existing_enable_sequence(self):
             self.assertEqual(inverter.write_and_poll_option.call_count, 2)
             self.assertEqual(base.errors, [])
 
+    def test_coordinator_with_partial_ownership_keeps_staged_sequence(self):
+        """A coordinator is identified before ownership checks, so it is never refused by them."""
+        from gateway import GATEWAY_COORDINATOR_TYPES
+
+        for kind in GATEWAY_COORDINATOR_TYPES:
+            inverter, gateway, base, wire = self.fixture()
+            gateway._discovery = {"CE123456789": {"type": kind}}
+            base.dashboard_index_app[TestCommandAck.SLOT_END] = None
+            self.apply(inverter)
+            self.assertFalse(any("inconsistent entity ownership" in error for error in base.errors), kind)
+            self.assertEqual(wire, [], kind)
+            self.assertEqual(inverter.write_and_poll_option.call_count, 2, kind)
+
     def test_invalid_time_or_pair_is_rejected_before_command(self):
         """The public paired method validates inputs before calling the command sink."""
         inverter, gateway, base, wire = self.fixture()