introduce a reference device annotation to group composable previews

[thebino]

📑 Description

Add an annotation to group possible composable previews to make the code more readable

✅ Checks

• My pull request adheres to the code style of this project
• My code requires changes to the documentation
• I have updated the documentation as required
• All the tests have passed

ℹ Additional Information

[github-actions]

App Coverage

File	Coverage [0.00%]	❌
ui/settings/src/main/kotlin/photos/network/ui/settings/SettingsScreen.kt	0.00%	❌
ui/settings/src/main/kotlin/photos/network/ui/settings/composable/ServerSetupItem.kt	0.00%	❌
ui/settings/src/main/kotlin/photos/network/ui/settings/composable/SettingsHeader.kt	0.00%	❌

Total Project Coverage	7.62%	❌