Use SimpleMonacoEditor for most inline editors

[colin-grant-work]

What it does

Closes #15218

Adds a new function createSimpleInline to the MonacoEditorProvider that returns an instance of SimpleMonacoEditor that is more customizable than our standard MonacoEditor, allowing customization of both services, which the MonacoEditor also does, and editor contributions, which the MonacoEditor does not, and 'simplicity', which the MonacoEditor also doesn't. Control of contributions is the more direct way to control the presence or absence, rather than behavior, of certain features: remove the inlay hints contribution, and the editor won't have inlay hints, etc.

See discussion on issue re: current design.

How to test

1. Three current inline editor use cases have been replaced: breakpoint widgets, AI chat input, and AI chat code snippet rendering.
2. Confirm that each of the three behaves as expected:

• breakpoint widgets should have code completion for the current context. (But NB that the code completion isn't currently as sophisticated as in the editor itself.
• AI chat input should have code completion for chat variables, etc.
• AI chat code snippets should still be colored according to the language in which they're written.

Note that currently, all three editors are instantiated with a full complement of both services and editor contributions - the primary difference in behavior is from setting isSimpleWidget to true; see discussion here.

Follow-ups

Breaking changes

• This PR introduces breaking changes and requires careful review. If yes, the breaking changes section in the changelog has been updated.

Attribution

Review checklist

• As an author, I have thoroughly tested my changes and carefully followed the review guidelines

Reminder for reviewers

• As a reviewer, I agree to behave in accordance with the review guidelines

[sdirix]

Looks good to me! I did not notice any regression.

I tested with the vim extension, and it worked although I had breakpoint editor and chat view open! Nice!