feat: enhance order handling in LighterGateway and introduce order identity normalization for improved precision and consistency

src/exchanges/lighter/order-feed.ts

@@ -0,0 +1,19 @@
+function isPlainObject(value: unknown): value is Record<string, unknown> {
+  return typeof value === "object" && value != null && !Array.isArray(value);
+}
+
+/**
+ * Determines whether a per-market websocket payload should reset the cached
+ * orders before applying its contents.
+ */
+export function shouldResetMarketOrders(bucket: unknown, snapshot: boolean): boolean {
+  if (snapshot) return true;
+  if (bucket == null) return false;
+  if (Array.isArray(bucket)) {
+    return bucket.length === 0;
+  }
+  if (isPlainObject(bucket)) {
+    return Object.keys(bucket).length === 0;
+  }
+  return false;
+}