feat(api-input): expose timeout/interpolation, fix 422 on light turn-on

- coordinator.update_source now auto-injects source_type from cached data so
  the server's discriminated-union body validates (was rejecting
  fallback_color updates with 422).
- Add Fallback Timeout (number) and Interpolation (select) entities per
  api_input CSS source.
- Light no longer zeros fallback_color on turn_off; state restored across
  HA restarts via RestoreEntity so the chosen default color persists.
- Bump manifest to 0.2.2 and update en/ru translations.

custom_components/ledgrab/select.py

@@ -29,6 +29,11 @@ async def async_setup_entry(
     coordinator: LedGrabCoordinator = data[DATA_COORDINATOR]
 
     entities: list[SelectEntity] = []
+    if coordinator.data:
+        for source in coordinator.data.get("css_sources") or []:
+            if source.get("source_type") == "api_input":
+                entities.append(ApiInputInterpolationSelect(coordinator, source, entry.entry_id))
+
     if coordinator.data and "targets" in coordinator.data:
         for target_id, target_data in coordinator.data["targets"].items():
             info = target_data["info"]
@@ -176,3 +181,64 @@ class BrightnessSourceSelect(CoordinatorEntity, SelectEntity):
             self._target_id,
             brightness={"value": 1.0, "source_id": source_id} if source_id else 1.0,
         )
+
+
+# --- api_input CSS source select entities ---
+
+INTERPOLATION_OPTIONS = ["none", "linear", "nearest"]
+
+
+class ApiInputInterpolationSelect(CoordinatorEntity, SelectEntity):
+    """LED count interpolation mode for an api_input CSS source.
+
+    Controls how the source resamples pushed colors when the target strip
+    has a different LED count than the input. Server accepts
+    ``none`` | ``linear`` | ``nearest``.
+    """
+
+    _attr_has_entity_name = True
+    _attr_icon = "mdi:vector-polyline"
+    _attr_options = INTERPOLATION_OPTIONS
+
+    def __init__(
+        self,
+        coordinator: LedGrabCoordinator,
+        source: dict[str, Any],
+        entry_id: str,
+    ) -> None:
+        super().__init__(coordinator)
+        self._source_id: str = source["id"]
+        self._entry_id = entry_id
+        self._attr_unique_id = f"{self._source_id}_interpolation"
+        self._attr_translation_key = "api_input_interpolation"
+
+    @property
+    def device_info(self) -> dict[str, Any]:
+        return {"identifiers": {(DOMAIN, self._source_id)}}
+
+    @property
+    def current_option(self) -> str | None:
+        source = self._get_source()
+        if not source:
+            return None
+        value = source.get("interpolation")
+        return value if value in INTERPOLATION_OPTIONS else None
+
+    @property
+    def available(self) -> bool:
+        return self._get_source() is not None
+
+    async def async_select_option(self, option: str) -> None:
+        if option not in INTERPOLATION_OPTIONS:
+            _LOGGER.error("Invalid interpolation option: %s", option)
+            return
+        await self.coordinator.update_source(self._source_id, interpolation=option)
+        await self.coordinator.async_request_refresh()
+
+    def _get_source(self) -> dict[str, Any] | None:
+        if not self.coordinator.data:
+            return None
+        for source in self.coordinator.data.get("css_sources") or []:
+            if source.get("id") == self._source_id:
+                return source
+        return None