Hugo template system

New template system in Hugo v0.146.0

See: New Hugo template system docs

A more detailed look at Hugo/Go templates: Go template basics.

Changes to the layouts folder:

• The _default folder is removed. Action required: Move all files in layouts/_default up to the /layouts root.

This is relevant to what I wrote in Create a custom Hugo image render hook. The directory structure I initially used was based on a response from Google AI — I broke my own rule in relying on that.