[enhancement]: Viewing-Editing button is better as a toggle

[ufuksarp]

Is there an existing issue for this?

• [X] I have searched the existing issues

What should this feature add?

This removes the extra click and makes the button more intuitive with a clearer view of the current state. Below is just a quick sketch to illustrate the idea, not the exact suggestion of the restyling:

Also this button should be positioned at top-left, which is much closer to the main work area than top-right. The current items at top-left should stay there.