fix: ensure the correct z-index for circle, rectangle, freehand

[JamesLMilner]

Description of Changes

Minor fixes to ensure z-indexs are correct for circle, rectangle and freehand modes. This is mostly an issue in the Leaflet adapter.

Link to Issue

No issue

PR Checklist

• [x] The PR title follows the conventional commit standard
• [ ] There is a associated GitHub issue
• [ ] If I have added significant code changes, there are relevant tests
• [ ] If there are behaviour changes these are documented