feat: support glob patterns in `editor.fileTree.allowEdits`

[AriPerkkio]

• Continues https://github.com/stackblitz/tutorialkit/pull/314

Adds support for users to specify one or multiple glob patterns in editor.fileTree.allowEdits.

---
type: lesson
title: Example
editor:
  fileTree:
    allowEdits:
      # Items in root
      - "/*"

      # Only "allowed-filename-only.js" inside "/first-level" folder
      - "/first-level/allowed-filename-only.js"

      # Anything inside "second-level" folders anywhere
      - "**/second-level/**"
---

When students attempt to create file that doesn't match these patterns, we show an error dialog:

[stackblitz[bot]]

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