code re-organization

src/utilities/layers.ts

@@ -0,0 +1,19 @@
+import { FilterSpecification } from "@maptiler/sdk";
+
+/**
+ * Creates an equality filter for Mapbox layer filtering
+ * @param id - The feature ID to match
+ * @returns A FilterSpecification for the given ID
+ */
+export const layerFilterEq = (id?: string | number) => {
+  return ["==", ["id"], id ? id : ""] as FilterSpecification;
+};
+
+/**
+ * Creates an inclusion filter for multiple feature IDs
+ * @param ids - Array of feature IDs to include in the filter
+ * @returns A FilterSpecification for the given IDs
+ */
+export const layerFilterIn = (ids: Array<string | number | undefined>) => {
+  return ["in", ["id"], ["literal", ids]] as FilterSpecification;
+};