Mercury tray resizes when entity browser modal dialogs are opened

Marking this critical because the mercury editor remains locked in the full-width mode even after reloading the page.

Dialogs should be behaving quite a bit better now.

I also moved some of the handlers around on resizing the sidebar tray, so that should better detect when the sidebar is open or closed. There is still one bug where if you collapse the sidebar and then start dragging it back open, it flies open to the width before it was collapsed. I thought it better to leave that as it stands currently and get more eyes on this sooner.

I believe this is undocumented at the moment, but you can configure dialog settings based on specific Paragraph types. This is found in Mercury Editor Dialog Settings. To do so, create a new object with the Paragraph's name appended with _form. For example:

_defaults:
  width: fit-content
  height: fit-content
  drupalAutoButtons: false
  dialogClass: lpb-dialog
  resizable: true
entity_ref_form:
  width: 600
  height: fit-content
  drupalAutoButtons: false
  dialogClass: lpb-entity-reference
  resizable: true
formatted_text_form:
  width: 800
  height: 600

I made some modifications to improve the experience of resizing the sidebar tray.

When collapsing and re-opening the tray using the button in the toolbar, the tray will now open at the default width. This makes the default width setting more relevant, because it's now possible to restore the tray to that default.

Resolved the issue where the tray popped open unexpectedly to a previously-stored value.

I think this is ready to merge if it looks good to others.

I tested the MR, and it fixes the reported issue.