* Unifies the different places creating a Layer Info Object or accessing "sharedassets".
* Fixes UEFN not able to access created LayerInfo objects in the ContentBrowser
* Adds the ability to create Landscape Layer Info Object as a regular asset (ie: without the landscape editor). Needed for example to create a Default LandscapeLayerInfoObject
#preflight 628ff637911f194ea743c6f3
#rb Jonathan.Bard
#ROBOMERGE-AUTHOR: luc.eygasier
#ROBOMERGE-SOURCE: CL 20395352 via CL 20395370 via CL 20395392 via CL 20395403
#ROBOMERGE-BOT: UE5 (Release-Engine-Staging -> Main) (v949-20362246)
[CL 20398733 by luc eygasier in ue5-main branch]