Add Completer Source to Inline similar to ListView

[JustinGrote]

Description of the new feature/enhancement

Listview shows the completer source as part of it's display, so you know if the completion is from history, azure, etc.

Inline should show the same using the same font as the completion and right justified as [Source] so that it's clear where the completion is coming from. This will be increasingly important as more extensions are added.

Mockup:

[theJasonHelmick]

My concern is that WLC (Whole Line Completions) often fill and wrap to the next line. Adding this to the end of the line seems like it would add more confusion without benefit as the person could hit F2 if needed to determine.