Align queries with 'nvim-treesitter'

I fear the upstream queries may be broken, somehow, as they don't work
with `--apply-all-captures` which should match the "last query wins"
matching behaviour of `nvim-treesitter`.

I also removed `locals.scm`, as `tree-sitter` and `nvim-treesitter` don't
agree on how to write it, and I don't really care about it.

It does mean that the highlights can't tell the difference between `int`
the built-in and `int` the type alias anymore, but that's a small
edge-case (and `nvim-treesitter` didn't support it anyway).

queries/folds.scm

@@ -8,9 +8,7 @@
   (let_expression)
   (function_declaration)
   (primitive_declaration)
-
   (record_type)
-
   (class_declaration)
   (class_type)
   (method_declaration)