- `TSQuery`: userdata object for parsed query.
- `vim.treesitter.Query`: renamed from `Query`.
- Add a new field `lang`.
- `TSQueryInfo`:
- Move to `vim/treesitter/_meta.lua`, because C code owns it.
- Correct typing for `patterns`, should be a map from `integer`
(pattern_id) to `(integer|string)[][]` (list of predicates or
directives).
- `vim.treesitter.QueryInfo` is added.
- This currently has the same structure as `TSQueryInfo` (exported
from C code).
- Document the fields (see `TSQuery:inspect`).
- Add typing for `vim._ts_parse_query()`.