Add integration with Session Replay product for native platforms

[tustanivsky]

This PR adds Session Replay product integration for platforms where sentry-native is used (desktop, both crashpad and native backends supported). The gameplay recorded in the rolling buffer before a crash is now delivered to Sentry as a separate session replay envelope (discoverable in the Replays dashboard and associated with the crash) instead of only being attached to the event as an MP4 file.

Example replay capture.

Key Changes

• The session-replay recorder now writes a small JSON metadata sidecar (replay-<id>.json) next to the rolling MP4.
• On crash, the recording's replay_id is set on the event's replay context so the crash and the replay are linked.
• The bundled sentry-native backend builds the replay_video envelope from the sidecar + MP4 and sends it to Sentry:
  • crashpad: writes the envelope to the run directory via the disk transport, where it is picked up on the next application launch.
  • native: uploads the envelope out of process during the same crashed session.
• Replay is enriched from the crash event's scope (tags, contexts, release, environment, user) and the matching trace id, so the it correlates with the crash's events/spans.

Known Limitations

• On Windows and Linux, when the crashpad backend (default) is used, the replay envelope is uploaded on the next application launch after the crash occurs. With the native backend (opt-in), the replay envelope is uploaded to Sentry during the same crashed session.
• On macOS, when the cocoa backend is used, the replay clip remains attached to the crash event as an MP4 attachment.

Depends on:

• feat(session-replay): upload replay envelope from the native crash daemon sentry-native#1809
• feat(session-replay): upload replay envelope on crash with crashpad, breakpad and inproc backends sentry-native#1842
• Add session replay API helpers app-runner#52

Related items

• Add experimental session replay capturing on Windows #1404
• Add experimental Session Replay capturing on Mac #1425
• Add experimental session replay capturing on Linux #1428
• Add experimental session replay capturing for Android #1386

[github-actions]

	Fails
🚫	Please consider adding a changelog entry for the next release.

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

Instructions and example for changelog

Please add an entry to CHANGELOG.md to the "Unreleased" section. Make sure the entry includes this PR's number.

Example:

## Unreleased

### Features

- Add integration with Session Replay product for native platforms ([#1445](https://github.com/getsentry/sentry-unreal/pull/1445))

If none of the above apply, you can opt out of this check by adding #skip-changelog to the PR description or adding a skip-changelog label.

Generated by 🚫 dangerJS against f39ee2a

[jpnurmi]

Is this ready to go, or waiting for a sentry-native release?

[tustanivsky]

Is this ready to go, or waiting for a sentry-native release?

Technically, this can be merged as-is. However, I'd like to add end-to-end tests for replay envelope capturing and to do that we'll first need to pull in the native changes introduced in getsentry/sentry-native#1809.

[cursor]

Cursor Bugbot has reviewed your changes and found 2 potential issues.

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

^{Reviewed by Cursor Bugbot for commit 48652af. Configure here.}