devtools: Allow highlighting elements from the inspector (#35822)

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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tests

Signed-off-by: Simon Wülker <simon.wuelker@arcor.de>

components/devtools/actors/inspector.rs

@@ -166,6 +166,8 @@ impl Actor for InspectorActor {
                 if self.highlighter.borrow().is_none() {
                     let highlighter_actor = HighlighterActor {
                         name: registry.new_name("highlighter"),
+                        pipeline,
+                        script_sender: self.script_chan.clone(),
                     };
                     let mut highlighter = self.highlighter.borrow_mut();
                     *highlighter = Some(highlighter_actor.name());