IDEA-58130 Improve editor performance during working with large files written in a single line

* Previously, on a document change in a soft wrapped line, soft wraps were recalculated for the whole line. Now recalculation starts from visual line,preceeding change location, and proceeds until the new visual layout starts to match the layout before the change.
* Some existing soft-wrap-related bugs were fixed (see added test cases)
external system: do not register duplicated library paths