chore: Update cspell and fix issues

- covert `cSpell.json` to `cspell.config.yaml`
- break up the word list into multiple dictionary files
- fix spelling issues
- Enable spell checking code for non-test files

docs/syntax/sankey.md

@@ -301,3 +301,5 @@ Graph layout can be changed by setting `nodeAlignment` to:
 - `center`
 - `left`
 - `right`
+
+<!--- cspell:ignore Ngas bioenergy biofuel --->