Whilst I cant offer any help, I too am trying to do the same.
Is there anyone with some knowledge on importing and using scripts that could help?
Its frustrating that it was once quite easy to do but now not.
It doesn't matter how I import the script, at runtime I just see this in the console:
Uncaught TypeError: Cannot set properties of undefined (setting 'L')
If I set the leaflet.js to import for events, I get an error at runtime and the following in the console...
scriptsInEvents.js:5 Uncaught TypeError: Cannot set properties of undefined (setting 'L')
at scriptsInEvents.js:5:145
at scriptsInEvents.js:5:150
domSide.js:24 [C3 runtime] Failed to load JavaScript code used in events. Check all your JavaScript code has valid syntax.
_InitDOM @ domSide.js:24