feat: updates @DevicePreviews to use the Devices object constants

[telpirion]

What I have done and why

• The @DevicePreviews annotation didn't show different form factors; they were always portrait. I changed the annotation so that it uses the constants from the Devices object.

[gemini-code-assist]

Summary of Changes

Hello @telpirion, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request significantly improves the preview capabilities within the application by updating the @DevicePreviews annotation to leverage standard device constants, ensuring a more accurate representation of UI across different form factors. It also introduces new previews for key screens and refactors build configurations, streamlining the development and testing process for Compose UI components.

Highlights

• Enhanced Device Previews: The @DevicePreviews annotation has been updated to utilize constants from the androidx.compose.ui.tooling.preview.Devices object, ensuring that previews now correctly display various form factors beyond just portrait mode.
• New Previews Added: Previews have been added for NiaApp.kt and ForYouScreen.kt (specifically for the onboarding and not-populated states) to improve visual testing and development workflow.
• Build Configuration Update: The core/datastore-proto/build.gradle.kts file has been cleaned up by removing redundant source set registration for protobuf generated files, and a new androidx-navigationevent-compose dependency has been added to app/build.gradle.kts.
• Conditional Rendering for Previews: The ForYouEntryProvider.kt now includes conditional rendering logic using LocalInspectionMode.current to provide mock data for ForYouScreen when in preview mode, simplifying preview setup.

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[gemini-code-assist]

Code Review

This pull request significantly improves the Jetpack Compose previews by updating @DevicePreviews to use standard Devices constants and adding new previews for NiaApp and ForYouScreen. The changes make the previews more robust and easier to maintain. I've also included a suggestion to refactor the preview setup in ForYouEntryProvider.kt to improve code clarity and reduce verbosity.

[telpirion]

Bad Code Assist, no donut

[dturner]

Thanks for the PR. Made a few suggestions and have a few questions.

[telpirion]

I removed all of the extra changes as they weren't pertinent to the primary purpose of this PR. Please take another look.

[dturner]

@telpirion Please could you help me understand the form factor previews a bit better?

The @DevicePreviews annotation didn't show different form factors;

Original code:

@Preview(name = "phone", device = "spec:shape=Normal,width=360,height=640,unit=dp,dpi=480")
@Preview(name = "landscape", device = "spec:shape=Normal,width=640,height=360,unit=dp,dpi=480")
@Preview(name = "foldable", device = "spec:shape=Normal,width=673,height=841,unit=dp,dpi=480")
@Preview(name = "tablet", device = "spec:shape=Normal,width=1280,height=800,unit=dp,dpi=480")
annotation class DevicePreviews

Genuine question, aren't these different form factors? Is there something to do with the density being the same that makes them lack form factor diversity?

they were always portrait.

The "landscape" and "tablet" specs both have width > height which makes them landscape - am I missing something? Or did you just mean that the desktop form factor wasn't present?

Did you intend to remove the "landscape" preview? Should we have a preview for the "phone in landscape" form factor?

Sorry for all the questions. Screenshot testing and previews for adaptive apps is a hot topic at the moment and I'd like to make sure I understand the space correctly and that we're providing best practices here.

One final thought, should we update the DefaultTestDevices (used for screenshot tests) to match the device previews?