[Figma Bridge] Exports can fail silently

Sometimes, the user clicks "Export" and then... nothing visible happens. They might see  an error message in the Developer Console, but designers don't often look there.

For example:

• QDS-4690
• QDS-6771
• QDS-6970

Is it possible to implement a global exception handler? Or some kind of watchdog that checks that the export process is ongoing/done?

It would be great to at least inform the user that something has gone wrong.