Fix #76151

Get rid of the "current match" debouncer because now the selection and focus are synced by the navigator anyway, and that's fine.
Now the only debounce is on the open event coming from the navigator.
Also, change the navigator onFocus to respect the browserEvent's preserveFocus which should be ok

This is broken and I don't really like this behavior anyway

Using `object` causes errors if we disable `suppressImplicitAnyIndexErrors`

By overriding _register in this case, we could end up invoking this function on a subclass that had not actually been inited yet (when `_toDispose` has not been set). I believe the overriding was an accident, so the fix is to remove it

Fixing errors related to https://github.com/microsoft/TypeScript/issues/31380

* new reg service and always on mnemonics

* missed one

* use new node module and accessibility service

* add typings

* adopt accessibility service

* make it lazy