Localized messages are generated into source, not a synthetic package

[pkongkha]

It did not release to stable yet, but need to fix it beforehand.
https://docs.flutter.dev/release/breaking-changes/flutter-generate-i10n-source

Also, should have l10n.yaml in the root directory of the project.
https://docs.flutter.dev/ui/accessibility-and-internationalization/internationalization

[pkongkha]

Currently, you can commit to this branch to see if it works or not.
https://github.com/VPNclient/VPNclient-app/tree/bugfix/vpnclient-engine-depencency

[WishyutC]

I test it work fine

[pkongkha]

Did not disabled synthetic package yet.

[WishyutC]

Fix it to load json file instead

[pkongkha]

The branch is not merged yet.