use light effect catalog to get device scenes for lan control

We default to querying the list of scene effects from the platform
API, but if you are running without the platform API credentials
(eg: want to run in LAN only mode) then we'd punt on getting
the list of scenes, even though we do actually have a way to
obtain that information to pave over gaps in the Govee API.

This commit adds a fallback to querying that light effect
catalog.

refs: #349

src/service/state.rs

@@ -595,6 +595,21 @@ impl State {
             }
         }
 
+        if let Ok(categories) = GoveeUndocumentedApi::get_scenes_for_device(&device.sku).await {
+            let mut names = vec![];
+            for cat in categories {
+                for scene in cat.scenes {
+                    for effect in scene.light_effects {
+                        if effect.scene_code != 0 {
+                            names.push(scene.scene_name);
+                            break;
+                        }
+                    }
+                }
+            }
+            return Ok(sort_and_dedup_scenes(names));
+        }
+
         log::trace!("Platform API unavailable: Don't know how to list scenes for {device}");
 
         Ok(vec![])