Editor overrides should operate on untyped editors only

[bpasero]

Related to #106012, the editor override service ideally:

• works on exclusively on IResourceEditorInput | IUntitledTextResourceEditorInput | IResourceDiffEditorInput

The would allow us to prevent this createEditorInput from running before the overrides are figured out:

vscode/src/vs/workbench/services/editor/browser/editorService.ts

Line 602 in f19843b

const result = this.doResolveEditorOpenRequest(editor, optionsOrGroup, group);

(also in other places). This helps prevent leaks in editor inputs.

[lramos15]

This is a duplicate of #121101. But I'll close the other one as I think the explanation here is nicer.

[lramos15]

The largest problem I'm currently running into with this is the diff editors. It seems that a lot of the consumers of the editor override service want names and descriptions from the typed diff editor input but by only allowing for IResourceDiffEditorInput we don't have that information.

[bpasero]

We can easily enrich the untyped editors with all the info we need.