"Create Layers From Assigned Materials" assigns existing LayerInfos at random

The automatic landscape layer assignment that is performed when using "Create Layers From Assigned Materials" just uses the first layer info it finds with the layer's name, which leads to maps referencing layer info objects "from other maps". In practice, this is mostly harmless, but it can be confusing and/or harmful when it comes to inter-plugin dependencies (with one landscape referencing layer info objects from another plugin).

Ideally, when performing the operation, the user would be presented with a dialog that lets him/her confirm the asset assignment or select another one or create a new layer info object. Since this will likely apply to several layers, it would also be nice to let the user select a folder from which all layer info objects will be auto-assigned and/or created (i.e. "bulk assignment").

Steps to Reproduce

Hello.

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We got a couple of levels using material instances of a general Landscape master material.

Pre 5.5 Layers would show up (In Landscape Mode->Paint) with empty assets slots when initially created.

As of 5.5 there are no empty layers visible and to be able to use them you need to press the button "Create Layers From Assigned Materials".

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The result from this is that when pressing the "Create Layers..."-button it assigns assets with matching names from what seems random paths.

The expected result should be empty slots (like previous versions) or at most limited to auto-assigned assets from <mapname>_sharedassets.

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How to repro:

Create Map A with instance of Material A with Landscape layers created and assigned.

Create Map B with instance of Material A.

Do a "Create Layers From Assigned Materials" to fill in the missing layers.

Resulting visible layers has assets assigned that belongs to Map A (or some other random matching assets).

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Kind regards

/Jörgen