fix(rivetkit): decode bridge errors with actor: null

Author: abcxff

rivetkit-typescript/packages/rivetkit/src/actor/errors.ts

@@ -237,7 +237,7 @@ export function decodeBridgeRivetErrorPayload(
 		if (!isRivetErrorLike(payload)) {
 			return undefined;
 		}
-		if (payload.actor !== undefined && !isActorSpecifier(payload.actor)) {
+		if (payload.actor !== undefined && payload.actor !== null && !isActorSpecifier(payload.actor)) {
 			return undefined;
 		}