Manual timezone is the single source of local-time truth (task 7e173881) (#285)

Co-authored-by: dev_agent <dev_agent@cubecraftlabs.com>
Co-committed-by: dev_agent <dev_agent@cubecraftlabs.com>

custom_components/nestquest/coordinator.py

@@ -111,6 +111,9 @@ def snapshot_from_api_payload(payload: dict[str, Any]) -> NestQuestSnapshot:
       through verbatim;
     - ``present`` and ``next_present`` pass through verbatim (the API
       resolved them through the same presence engine server-side);
+    - ``timezone`` (the API's effective application timezone) passes
+      through verbatim for the cards' date and clock; an API older than
+      the field omits it, which reads as ``""`` (the cards' fallback);
     - the instance list is rebuilt IN ORDER, so the panel payload the
       sensors emit matches the route's order byte for byte.
 
@@ -161,6 +164,7 @@ def snapshot_from_api_payload(payload: dict[str, Any]) -> NestQuestSnapshot:
         today_iso=payload["today_iso"],
         children=tuple(children),
         cycle_day=payload["cycle_day"],
+        timezone=payload.get("timezone", ""),
     )
 
 

custom_components/nestquest/core/snapshot.py

@@ -96,6 +96,11 @@ class NestQuestSnapshot:
     today_iso: str
     children: tuple[ChildDaySnapshot, ...]
     cycle_day: int
+    #: The application timezone the admin stored (``""`` when unset —
+    #: the host's local time; the API publishes its effective zone in
+    #: its place, api/host_zone.py).  The panel cards format their
+    #: visible date and clock in it; it never re-resolves the day itself.
+    timezone: str = ""
 
 
 def _cycle_day(
@@ -319,4 +324,5 @@ async def build_snapshot(
         today_iso=today_iso,
         children=tuple(snapshots),
         cycle_day=_cycle_day(patterns, children, today),
+        timezone=settings.timezone,
     )

custom_components/nestquest/sensor.py

@@ -441,6 +441,10 @@ class NestQuestHouseholdDueTodaySensor(_NestQuestHouseholdSensor):
                 for child in data.children
             },
             "child_roster": _child_roster(data.children),
+            # The API's effective application timezone ("" only when
+            # it could not name one): the panel cards format their
+            # visible date and clock in it.
+            "timezone": data.timezone,
         }