Make behaviour of Trust Boundary Boxes more reasonable

[boomer41]

Summary:

Fixes #1723.
Split from #1718

When accidentally mis-clicking to an empty space, the box gets selected.
To un-select it I have to scroll to somewhere where the box is not, click on an empty space, and return.
I can not select any other node inside the box until the box is deselected.

Additionally, the left margin of the box label seems a bit "random".
It is somehow floating, but not centered nor fixed to any edge.

Description for the changelog:

• Trust Boundary Boxes will no longer get selected when clicking on an empty space inside the box. To select a box, click on the border.
• Aligned the label of Trust Boundary Boxes on the top left side of the box

Declaration:

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• content meets the license for this project
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Other info:

[jgadsden]

This is a change to the behavior of the trust boundary boxes and needs discussion and thinking through, so putting ths pull request into draft

The existing trust boundary box behavior is as designed / expected, but I understand totally that it is difficult to suit every user, hence discussion is needed before a silent change like this is introduced

[github-actions]

This PR is stale because it has been open 21 days with no activity. Remove stale label, or add a comment, otherwise it will be closed in 7 days

[boomer41]

bad bot