* Theming for dirty tabs

* Improve border for dirty tabs
1. Make it thinner
2. Add a setting to disable it
3. Use 4 colors (activeFocused, activeUnfocused, inactiveFocused, inactiveUnfocused)
4. Move part of logic

* Hot apply of setting `dirtyTabBorder`

* Rename the setting

* Add default dirty border for all themes

* 3 of the 4 colors should be derived from the one main color

* Rename `dirty` to `modified`

* Rename `modifiedActiveFocusedBorder` to `modifiedBorder`

* Add modified border color for built-in themes

* More contrast

* Applying style directly on element

* Changing only color

* Using full border

* Using existing div for border styling

* Add setting to telemetry

* Uncomment cleanup code

* tweak colors and descriptions

* 💄

update internal API to allow parameter label to be an offset-range of its the signature label, #56337

Fixes #60005

Introduces the concept of a re-trigger character to the signature help provider. This is a seperate set of characters that are registered with the provider. Typing a retrigger character fires a new signature help request if signature help is already showing.

#54972

The previous solution involved an own solution with an array of
disposables. The new solution makes use of the _register-method from the
Displosable class.

#53989

* enable dynamic menu on linux/windows
workaround to fix #33457

* Address feedback

* other comment

fixes #53989

This reverts commit 686e7416.