Logging out from an instance using the immersive editor makes the editor drawer linger

[cstns]

Current Behavior

The immersive editor drawer remains visible.

Expected Behavior

the drawer should not be present

Steps To Reproduce

log out from a node red instance while using the immersive editor.

Environment

• FlowFuse version: 2.8.0
• Node.js version: n/a
• npm version: n/a
• Platform/OS: n/a
• Browser: n/a

Have you provided an initial effort estimate for this issue?

I have provided an initial effort estimate

[cstns]

The immersive editor, running in an iframe, was redirecting to the FlowFuse instance overview page when users clicked logout, resulting in a scenario where you'd have the main app nested in itself.

The fix implies to add an interceptor when the nr-editor is running in an embedded mode and emit a 'logout' postMessage event which gets picked up by the FlowFuse application which in turn redirects the entire page to the instance overview page.