Load Asset/Shot LOP use Generic Loader as internal building block

[BigRoy]

Is there an existing issue for this?

• I have searched the existing issues and added correct labels.

Please describe the feature you have in mind and explain what the current shortcomings are?

With the Generic Loader implementation now merged it's time to refactor the Load Asset LOP and Load Shot LOP to also use it.

Suggested implementation?

• Use the Generic Loader internally to Load Asset LOP and Load Shot LOP
• Add support to still manage the Thumbnail on the "outer node", e.g. using a thumbnail_node parm that thumbnails are applied to that node instead of the generic loader internally. The default value for that parm would then be the node itself. (We could technically spawn of thumbnail also into a separate node, but I wouldn't bother with that for now)
• Make sure LOPs context options still correctly work.
• Make sure the changes are backwards compatible.
• The Loader and Scene Inventory (AYON > Load... and AYON > Manage...) should still work and nicely detect them
  • This of course also needs to be backwards compatible with existing LOPs, etc.

Describe alternatives you've considered:

No response