fix(core): Make node execution order configurable, and backward-compatible (#6507)

* fix(core): Make node execution order configurable, and backward-compatible

* ⚡ Also add new Merge-Node behaviour

* ⚡ Fix typo

* Fix lint issue

* update labels

* rename legacy to v0

* remove the unnecessary log

* default all new workflows to use v1 execution-order

* remove the controller changes

* clone default settings to avoid it getting modified

---------

Co-authored-by: Jan Oberhauser <jan.oberhauser@gmail.com>

packages/nodes-base/nodes/Merge/v1/MergeV1.node.ts

@@ -30,7 +30,6 @@ const versionDescription: INodeTypeDescription = {
 	inputs: ['main', 'main'],
 	outputs: ['main'],
 	inputNames: ['Input 1', 'Input 2'],
-	forceInputNodeExecution: true,
 	properties: [
 		oldVersionNotice,
 		{