Fixes #23015

Fixes #19758

Implement Windows terminal shell selector

Allow TreeModels to expand items as they are initially loaded, rather than expanding them later, which is much slower

- fix its flakiness
- add test-int-mocha so .integrationTest.js files can be run separately from code.sh integration tests.
- make all.js support globs with --run
- Fix #22512

fixes #20397
fixes #17526