debugger_ui: Improve some elements of the UI (#43344)

- In the launch tab of the new session mode, I've switched it to use the
`InputField` component instead given that had all that we needed
already. Allows for removing a good chunk of editor-related code
- Also in the launch tab, added support for keyboard navigation between
all of the elements there (dropdown, inputs, and switch component)
- Added some simple an empty state treatment for the breakpoint column
when there are none set


https://github.com/user-attachments/assets/a441aa8a-360b-4e38-839f-786315a8a235

Release Notes:

- debugger: Made the input elements within the launch tab in the new
session modal keyboard navigable˙.

crates/debugger_ui/src/session/running/breakpoint_list.rs

@@ -1407,7 +1407,6 @@ impl RenderOnce for BreakpointOptionsStrip {
 
         h_flex()
             .gap_px()
-            .mr_3() // Space to avoid overlapping with the scrollbar
             .justify_end()
             .when(has_logs || self.is_selected, |this| {
                 this.child(