🧩 JSON Merge Patch

About RFC 7396: A JSON Merge Patch is a JSON value that describes changes to a target JSON document. If the patch is an object, every member replaces or adds to the target; null values delete the member. If the patch is any other value (array, string, number, boolean, null), it replaces the target entirely. Arrays are replaced, not merged — for element-level operations use JSON Patch (RFC 6902) instead.