KernelCatalog

Every field kernel, read from `catalog.yaml` in libfield's resources (field-presentation §FVK-1, §FVK-2).

In the namespace field. Declared in src/libs/libfield/field/KernelCatalog.hpp.

Detailed description

A new kernel is a `.glsl` file and a catalog entry. The catalog checks each entry and reports what it refuses; the others load.