chore: use 'files' instead of .npmignore

[midgleyc]

What is the purpose of this pull request?

• Documentation update
• Bug fix
• New rule
• Changes an existing rule
• Add autofixing to a rule
• Other: build simplification

What changes did you make? (Give an overview)

Change build to use files over .npmignore.

.npmignore lists the files that should not be in the build, and can easily go out of date (and has) because it needs updating every time a file is added that shouldn't be in the build.

files in package.json lists the files that should be in the build, and can be kept up to date more easily.

I include the rules folder, and the files which are always included automatically.

[brettz9]

This looks good to me if you want to first resolve the conflicts, however.

[voxpelli]

Suggested change

	"rules"
	"rules/**/*.js",
	"index.js"

I would go with this

[midgleyc]

that would miss rules/lib/is-member-call-with-object-name which perhaps does want to end with .js?

[brettz9]

Yes, sorry, that does want to end with .js. Addressed in the TypeScript PR, but I can supply a separate PR to address.

[midgleyc]

I've redone the changes on the tip of main.

If you add TypeScript types, you'll also want to add index.d.ts and rules/**/*.d.ts to the array.

Except the previously mentioned file lacking .js, the only files removed (compared to a previous npm pack) are .eslint-doc-generatorrc.js and CHANGELOG.md.