fix: pass the results of userChoice to the developers

[QC-L]

There are times when we need to handle different logic based on the result of userChoice.

$pwa?.install().then((userChoice) => {
	if (userChoice.outcome === 'accepted') {
		console.log('accepted install');
	}
})

[userquin]

@QC-L thx ❤️

The type can be undefined in the promise, anyone can call the install method at any time

[userquin]

Note: if the user installs the app, some platforms will close the app in the browser and will open the installed PWA (for example Chrome and Edge in Windows Desktop).

Updating docs...