Flattened PerformanceCollectionData

[stefanosiano]

📜 Description

merged CpuCollectionData and MemoryCollectionData into PerformanceCollectionData
PerformanceCollectionData now contains timestamp in nanoseconds, so we don't store Date objects anymore

💡 Motivation and Context

Closes #4303
We are not storing date objects in memory anymore, and we also avoid instantiating multiple objects

💚 How did you test it?

📝 Checklist

• 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.
• I updated the wizard 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.

🔮 Next steps

[github-actions]

Performance metrics 🚀

	Plain	With Sentry	Diff
Startup time	428.00 ms	446.64 ms	18.64 ms
Size	1.58 MiB	2.09 MiB	518.63 KiB

Previous results on branch: internal/flatten-performance-data

Startup times

Revision	Plain	With Sentry	Diff
98e03f7	400.54 ms	441.78 ms	41.24 ms

App size

Revision	Plain	With Sentry	Diff
98e03f7	1.58 MiB	2.09 MiB	518.59 KiB