Show editor indexes in the Open Editors view

[duphyf]

The editor tab bar supports workbench.editor.showTabIndex, which helps users identify tab indexes for keyboard-driven navigation.

However, when editor tabs are hidden with:

"workbench.editor.showTabs": "none"

the Open Editors view can become the main visible representation of open editors and editor groups. Currently, this view does not provide a way to show the editor indexes.

Proposal

Add a setting explorer.openEditors.showTabIndex

When enabled, the Open Editors view should show the 1-based index of each editor within its editor group.

For example:

Group 1
  1: main.ts
  2: package.json

Group 2
  1: app.tsx
  2: routes.ts

The displayed index should correspond to the editor's actual index within its editor group, matching the index used by editor navigation commands.

This would make the Open Editors view more useful for keyboard-driven workflows, especially when editor tabs are hidden.

Example: