feat(examples): Add Paparazzi snapshot setup to instrumentation sample

[runningcode]

Summary

• Apply app.cash.paparazzi 2.0.0-alpha04 to the android-instrumentation-sample and enable sentry { snapshots { enabled.set(true) } }
• Add @Preview composables (HomeTextPreview, DetailsTextPreview) so the snapshot scanner has something to discover
• Add a CI step in the pre-merge workflow to record and upload snapshots when SENTRY_AUTH_TOKEN is available

#skip-changelog

🤖 Generated with Claude Code

[github-actions]

Semver Impact of This PR

🟡 Minor (new features)

📋 Changelog Preview

This is how your changes will appear in the changelog.
Entries from this PR are highlighted with a left border (blockquote style).

---

This PR will not appear in the changelog.

---

_{🤖 This preview updates automatically when you update the PR.}

[github-actions]

	Messages
📖	Do not forget to update Sentry-docs with your feature once the pull request gets approved.

Generated by 🚫 dangerJS against aa263dc

[cursor]

Snapshot upload runs redundantly on all three OS matrices

Medium Severity

The new "Record and upload snapshots" step runs on all three matrix OSes (ubuntu-latest, macos-latest, windows-latest) since it only guards on SENTRY_AUTH_TOKEN. Paparazzi snapshot rendering can produce platform-dependent output (e.g., font rendering differences), so uploading from all three OSes can result in non-deterministic snapshots overwriting each other in Sentry. This likely needs a runner.os condition (similar to the existing preMerge step) to restrict it to a single OS.

 

^{Reviewed by Cursor Bugbot for commit c0d0a21. Configure here.}

[sentry]

Bug: Calling rememberNavController() inside @Preview composables will crash Paparazzi snapshot tests because a ViewModelStoreOwner is not available in the test environment.
_{Severity: HIGH}

Suggested Fix

To prevent the crash, do not call rememberNavController() directly within @Preview functions. Instead, create and pass a mock NavController to the composable under test. For example: HomeText(navController = NavController(LocalContext.current), ...). Alternatively, you can wrap the preview composable with a CompositionLocalProvider to supply a fake ViewModelStoreOwner for the test environment.

Prompt for AI Agent

Review the code at the location below. A potential bug has been identified by an AI
agent.
Verify if this is a real issue. If it is, propose a fix; if not, explain why it's not
valid.

Location:
examples/android-instrumentation-sample/src/main/java/io/sentry/samples/instrumentation/ui/ComposeActivity.kt#L66-L68

Potential issue: The `@Preview` composables `HomeTextPreview` and `DetailsTextPreview`
directly invoke `rememberNavController()`. This function internally depends on
`LocalViewModelStoreOwner.current` to get a `ViewModelStoreOwner`. The Paparazzi
snapshot testing environment, which runs on a JVM, does not provide this context by
default. As a result, attempting to generate snapshots for these previews will cause a
runtime crash, likely an `IllegalStateException`. This crash will cause the
`recordPaparazziStagingDebug` Gradle task to fail, which in turn will block the CI
workflow step `sentryUploadSnapshotsStagingDebug` from completing.

_{Did we get this right? 👍 / 👎 to inform future reviews.}

[cursor]

Cursor Bugbot has reviewed your changes and found 1 potential issue.

There are 2 total unresolved issues (including 1 from previous review).

^{❌ Bugbot Autofix is OFF. To automatically fix reported issues with cloud agents, enable autofix in the Cursor dashboard.}

^{Reviewed by Cursor Bugbot for commit 951e483. Configure here.}

[cursor]

Preview composables may crash in Paparazzi rendering context

Medium Severity

HomeTextPreview and DetailsTextPreview call rememberNavController(), which internally uses checkNotNull(LocalViewModelStoreOwner.current). Paparazzi's rendering context may not provide LocalViewModelStoreOwner, causing an IllegalStateException at snapshot recording time. This is a known class of issues with navigation components in Paparazzi (cashapp/paparazzi#635). Simpler preview-safe composables that don't require NavController would avoid this risk.

Additional Locations (1)

• examples/android-instrumentation-sample/src/main/java/io/sentry/samples/instrumentation/ui/ComposeActivity.kt#L83-L88

 

^{Reviewed by Cursor Bugbot for commit 951e483. Configure here.}

[sentry]

Bug: The use of .first() to find the Paparazzi snapshots directory is unsafe and will throw an exception if the directory is not found in the test task's outputs.
_{Severity: MEDIUM}

Suggested Fix

Replace the unsafe .first() call with .firstOrNull(). This allows for checking if the directory exists and throwing a more informative GradleException if it is not found, preventing unexpected build failures.

Prompt for AI Agent

Review the code at the location below. A potential bug has been identified by an AI
agent.
Verify if this is a real issue. If it is, propose a fix; if not, explain why it's not
valid.

Location: .github/workflows/pre-merge.yaml#L49-L52

Potential issue: The code uses `.first { file -> file.name == "snapshots" }` to find a
snapshots directory within a test task's output files. This will throw a
`NoSuchElementException` if no file with that name is found, causing the build to fail.
Standard test tasks do not typically produce a "snapshots" directory in their output,
and while the Paparazzi library might configure this, it's an undocumented behavior.
This makes the code fragile and reliant on a specific, unconfirmed output structure of
an alpha version of a library.