Appkit+Qt+LibWeb+LibWebView: Dock inspector in browser window

[neil-ptr]

Description

This PR allows for the inspector to be docked in the window beside the web content. There are some issues with the <select/> tag dropdowns that are within the inspector but didn't address them as they were out of scope for this feature.

This PR also sets the ground work to have up, down, left, right and windowed inspector positions in a <select/> within the inspector and also have the browser remember what the last size and position that inspector was in last which I hope to follow up this PR with

Appkit

VideoSmaller.Sept.19.Screen.Recording.mov

Qt

VideoSmaller.Screen.Recording.Sept.19.mov

[ladybird-bot]

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[AtkinsSJ]

Hi! Welcome to Ladybird. :^)

This is a cool feature, thanks for working on it!

I must admit that objective-c is still a mystery to me, and I'm not that familiar with Qt either, so those changes will need someone else to review.

Most of my comments are about commit style really - generally I think this is good. When correcting a change you made earlier in the same PR, please make that correction to the original commit. You can find a good guide to doing that here, or ask for help here or on Discord if you get stuck. (Git is very good at letting you undo mistakes, it's just bad at making it clear how to do so.)

[neil-ptr]

@AtkinsSJ Thanks for the review! I cleaned up the commits and addressed your comments