Add prefix for shared preference usage

[Clon1998]

Based on my comment in #19, it is not possible to use multiple live activities simultaneously due to the use of UserDefaults to transfer data from Flutter to the live activity. However, to resolve this issue, I added a prefix to all of the stored values in UserDefaults using the ID set via LiveActivitiesAppAttributes. This modification enables the use of multiple live activities without any conflict.

For now, this is just a discussion. I was able to successfully test my implementation for local creations and updates but not for remote updates yet.

[istornz]

Thanks for your PR @Clon1998, I think creating a prefix is the good idea.

An another fix will be to revert back usage of dynamic LiveActivities attributes but I think UserDefaults is the better way to transmit typed data to Swift code (discussion here).

I will test your PR ASAP 👍

[Clon1998]

Thanks for your PR @Clon1998, I think creating a prefix is the good idea.

An another fix will be to revert back usage of dynamic LiveActivities attributes but I think UserDefaults is the better way to transmit typed data to Swift code (discussion here).

I will test your PR ASAP 👍

I thought about the dynamic attributes. But this might break the remote updates for other devs. This change already is a breaking change as it will require all users to include the prefix before using any key.

[Clon1998]

Just tested APNs/Remote updates. They now work as expected for multiple live activities :)