This change connects the `HighlighterActor` from the devtools with the
document, which will draw a blue rectangle over any highlighted dom
node.
https://github.com/user-attachments/assets/571b2dab-497f-4102-9e55-517cdcc040ba
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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes do not require tests because we don't have devtools
tests
Signed-off-by: Simon Wülker <simon.wuelker@arcor.de>