Also fix asset references persisting when applying a property access binding
#jira UE-116509 - Unable to create empty Blend Space Graphs in the Anim Graph
#rb Jurre.deBaare
[CL 16657336 by Thomas Sarkanen in ue5-main branch]
Unified the approach to gathering assets and spawning nodes from them. Previously each had its own slightly unique code doing similar things.
Note that with this change it is now possible to directly spawn 'evaluator' style nodes from the context menu instead of relying on a context menu conversion step.
Also tweaked icons, tooltips and titles for consistency
#rb Jurre.deBaare
[CL 16434364 by Thomas Sarkanen in ue5-main branch]
Added a new animation graph node that hosts its own UBlendSpaceBase. Modified UBlendSpaceBase to allow for pose links to be evaluated as the sample points.
The new blend space graphs can be spawned from existing UBlendSpace and UBlendSpace1D assets, or they can be created from scratch, or they can be converted from existing blendspace player nodes via the context menu.
Fixed anim node conversion functions so that their transactions work correctly.
Updated FBlueprintEditorUtils::IsGraphNameUnique to allow it to work with any object as the outer, not just UBlueprint. UBlueprint still has a special case for functions and events. This is to support GenerateUniqueGraphName within a scope (e.g. an outer graph).
Formalized the concept of 'node sub-graphs' (as well as the composite node pattern a little). Previously a number of known node types that contained sub-graphs (e.g. UK2Node_Composite) had special case logic for dealing with node/graph deletion etc. Now any node can opt into this behaviour via the GetSubGraphs() override.
Added status bar readouts for the blendspace grid, so we dont have to stuff the prompts into the tooltip any more.
Moved anim BP related APIs out of FBlueprintEditor. They are always used via FAnimationBlueprintEditor.
Refactored graph title bar widget creation out into a function to allow other document tab factories to create it.
Altered breadcrumb trail click callbacks and SMyBlueprint::ExecuteAction to always JumpToHyperLink rather than calling OpenDocument directly. This allows unknown (to FBlueprintEditor) document types that reference objects to be correctly jumped to using the breadcrumb trail. Derived asset editors (i.e. FAnimationBlueprintEditor) can intercept the JumpToHyperlink call to ensure that the correct document is presented (i.e. the correct tab payload is generated).
Instead of making yet another bunch of duplicated code for handling the various alpha blend options, refactored this into FAnimGraphNodeAlphaOptions (for editor code) and FAnimNodeAlphaOptions (for runtime code).
Added OnCopyTermDefaultsToDefaultObject for per-node copying of default values from editor node to runtime node, rather than another special-case in the compiler.
#rb Jurre.deBaare,Phillip.Kavan
[CL 15177316 by Thomas Sarkanen in ue5-main branch]
