Delete minimal catalog examples

[josemontespg]

From the review of #1405

@ditman

I think we should remove the "minimal" catalog and examples. They don't add much value once the renderer is fully built (instead, they add maintenance burden like here)

[ditman]

I actually removed it from Lit a while ago:

6c0296d

[ditman]

PS: I actually removed the "minimal" catalog implementation from everything lit, even the a2ui_explorer demo. There were some hacks in the code needed to load the appropriate examples and catalog, and I removed everything. 🔥🔥🔥