Groups Nodes replace Functions in Visual Scripting

Groups Nodes replace Functions
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Grouping of Nodes in a chain should be allowed to simplify the process of creation of Node Units and increasing reusability of parts of the Visual Scripts.

Quick Mockup.

> _Group Nodes should be stored as custom Nodes that are accessible from the same drop down for searching the Nodes and also allow for saving and loading groups as resources for use as custom nodes all across the project._

Probably even have a default folder where we can place all the Grouped Node(Custom Node) Resources that we want to be accessible across the project as custom nodes, automagically.
This would remove the need to newbie users to learn how to create Tool Scripts.

Details
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The Groups will be simple and clean and will act like bookmarks that will take us to the respective Group Node Structure we double click on.

The Groups will be a much simpler concept compared to functions but will technically use the same structure/codebase. It will also the first step towards addition of Unified Visual Script editor Graph.

Being able to save these can come extremely handy, such as having a module for simple visual script functions required and even Visual Shader node groups.