Fix treesit-indent-region

Fix treesit-indent-region

* lisp/treesit.el (treesit-simple-indent-presets): Remove extra comma.
(treesit--indent-1): Return (ANCHOR . OFFSET) instead of column.
(treesit-indent): Accept (ANCHOR . OFFSET) from treesit--indent-1.
(treesit--indent-region-batch-size): Reduce to 400.
(treesit-indent-region): Put a marker on each line's ANCHOR and
compute the indentation with ANCHOR + OFFSET.  Precomputing column
gives wrong indentation when the ANHOR line doesn't have correct
indent yet.