In-editor debugger has broken options when running multiple instances/sessions

[SaracenOne]

Godot version

0ca8542

System information

Windows 11

Issue description

The in-editor debugger has several bugs when debugging with multiple instances and operating on an instance other than the first one:

• The debug menu containing options such as step, break, and continue will cause an error when used on a session other than the first one and will not grey out the correct contextual options.
• Attempt to delete breakpoints via the menu in the lower right tree will not work for any session tab other than the first one.
• When switching sessions to a session that isn't breaked, it will still show the yellow arrow indicating the execution line for the previous session.

Steps to reproduce

Run a game with the multiple instances option and attempt to do the following things described in the issue description.

Minimal reproduction project

N/A