Add data from transaction root span to trace.context.data

[lbloder]

:scroll: Description

Add root span data to traceContext when SentryTransaction is created

:bulb: Motivation and Context

Fixes #3626

:green_heart: How did you test it?

Modified existing serialization tests

:pencil: Checklist

• [ ] I reviewed the submitted code.
• [ ] I added tests to verify the changes.
• [ ] No new PII added or SDK only sends newly added PII if sendDefaultPII is enabled.
• [ ] I updated the docs if needed.
• [ ] Review from the native team if needed.
• [ ] No breaking change or entry added to the changelog.
• [ ] No breaking change for hybrid SDKs or communicated to hybrid SDKs.

:crystal_ball: Next steps

[github-actions[bot]]

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

Generated by :no_entry_sign: dangerJS against b5e06918d17ec0eda498bfcd8cefccf947272526

[github-actions[bot]]

Performance metrics :rocket:

	Plain	With Sentry	Diff
Startup time	429.10 ms	495.08 ms	65.98 ms
Size	1.70 MiB	2.35 MiB	660.50 KiB

[lbloder]

Closed in favor of #3735