Prevent selecting the hovered node if the mouse is not inside the inspector dock

[AeioMuch]

Fix #94320
Also fixed the fact that the hovered&inspected node was not added to the selection history.

It will only select the hovered&inspected node if the mouse is inside the inspector at the end of the drag.
To reinspect the current selection, I went with the method of reselecting everything. Sadly selecting nodes is a bit slow if you select a lot of them, but that's a general issue.

I also moved the code that was happening when the mouse button was released, inside the NOTIFICATION_DRAG_END instead, to centralize stuff more. This made me realize there was a duplicate call to _reset_hovering_timer() left, and also a signal connection that was useless (_reset_hovering_timer() is already called in _handle_hover_to_inspect() anyway), and more importantly not connected to correct thing so it was not working.

[KoBeWi]

Something is wrong:

godot.windows.editor.dev.x86_64_qNPYLuaKYp.mp4

The selection goes back to dragged node even if it's assigned.

[AeioMuch]

Ah, thank you for noticing that! It looks like the check to see if the mouse is inside was off somehow. I was always testing to drop in a property that was not at the top, and that worked, but indeed when the mouse was at the top it was considered outside the inspector dock. I made some changes and it look to work properly now, also tested with the inspector dock floating and it worked also.

[akien-mga]

Thanks!