Break up the concept of normalizing a path and trying to get the on disk path of a resource. Needed for handling case insensitivity

This object is shared between all languages

Fix preferences smoketest - this test was opening app.js by clicking in the explorer, but app.js ended up scrolled half out off the view. Instead of clicking the row, it clicked the explorer view header and collapsed the file tree. Use quickopen to open it instead

fixes #51148

fixes #38746

fixes #38496

fixes #51137

fixes #48110

#51135