Dropdown Widget Improvements

[AdRiley]

This issue covers a number of improvements to the dropdown widget (Some may already be covered by https://github.com/enso-org/enso/issues/8708)

### Tasks
- [ ] Arrows for widgets: they should be visible only when widget is hovered + they should be a little smaller and less vivid.
- [ ] Drop downs should show code. (e.g. Right_Exclusive not Right Exclusive)
- [x] When an option is selected on the dropdown with a mouse click, the selection should be made and the dropdown immediately closed
- [ ] If there are a small number of items in the dropdown the height should shrink
- [ ] If there are a larger number of items in the dropdown the scrollbar should appear. The last item shoudl be half cropped.
- [ ] Dropdown shoud have a 2px border (Confirm the 2px with Figma design)
- [ ] The internal border radious should be constant
- [ ] Remove "sort" arrows in drop-down list (up/down)
- [ ] The dropdown triangle for constructors with arguments should be under the constructor name not centered.

[farmaazon]

Moved more complex points to #9058.

[enso-bot[bot]]

Michael Mauderer reports a new STANDUP for yesterday (2024-02-22):

Progress: Started working through the design changes. It should be finished by 2024-02-26.

Next Day: Next day I will be working on the #8995 task. Continue on task

[enso-bot[bot]]

Michael Mauderer reports a new STANDUP for the provided date (2024-02-23):

Progress: Fixed almost all issues, besides some smaller design questions that require further feedback. Some parts took longer than expected due to some debugging involved in tracking down some data transformation. It should be finished by 2024-02-26.

Next Day: Next day I will be working on the #8995 task. Finish task, open PR.

[enso-bot[bot]]

Michael Mauderer reports a new STANDUP for yesterday (2024-02-26):

Progress: Finalised implementation, fixed some tests and opened PR. It should be finished by 2024-02-26.

Next Day: Next day I will be working on the #8481 task. Start next task.