* Get pluginmeta mostly moved over to pkg/plugins/plugindef
* Remove dead func
* Fix up pfs, use sync.Once in plugindef
* Update to latest thema
* Chase Endec->Codec conversion in Thema
* Comments on slash header gen; use ToSlash
* Also generate JSON schema for plugindef
* Generate JSON Schema as well
* Fix slot loading from kindsys cue decls
* Remove unused vars
* skip generating plugin.schema.json for now
Co-authored-by: Marcus Efraimsson <marcus.efraimsson@gmail.com>