#94506

fixes #91602

refs #90468

For #81574

Based on https://stackoverflow.com/questions/59384319/typescript-get-typeof-generic-constructor

* migrate search to use new setting

* rename

* add getViewLocation api to vds for search

* remove unreferenced location option

* wip 2

* use viewlet stubs

* fix layering issue

* fix saveState and contextmenus

* move context menu logic into panecomposite

* revert tasks.json

* tasks again

* add showHeaderInTitleWhenSingleView values

* patch tests

* some cleanup

* more cleanup

* start view

* merging conflicts

* fix title and dnd

* adding missing api surface to pane composite

* additional merge resolution

* rename splitview panels to panes

* rename files

* customViewPane

#84715

Part of #81574

Makes the `createInstance` function signature more strict. Previously it inferred the argument types based on the actual argument values passed to `createInstance`. Instead, we now infer them from the constructor signature itself

Readonly helps out with TS's type guards and is also a good best practice. Specifically, readonly strings/numbers have their literal type instead of a generic `string` | `number` type, which can help catch dead code and some common programming mistakes

 #78168