Also update the type annotation of TSNode:id(), which returns a string,
not an integer.

Problem: Only injections under the top level tree are found.

Solution: Iterate through all trees to find injections. When two
injections are contained within the same node in the parent tree, prefer
the injection with the larger byte length.

When parsing with a range, languagetree looks up injections and adds
them if needed. This explicitly invalidates parser, making `is_valid`
report `false` both when including and excluding children.

This is an attempt to describe desired behaviour of `is_valid` in tests,
with what ended up being a single line change to satisfy them.

Co-authored-by: Wansmer <wansmer@gmail.com>
Co-authored-by: Andrew Voynov <andrewvoynov.b@gmail.com>
Co-authored-by: David Moberg <david.moberg@mediatek.com>

Problem:  Visual highlight is inconsistent on a folded line with
          treesitter foldtext.
Solution: Don't added Folded highlight as it is already in background.