Report used memory/max used memory

[ueman]

Problem Statement

In order to better understand the memory usage, Sentry should report the used memory of an application.

Solution Brainstorm

Dart offers to query some memory information:

• https://api.dart.dev/stable/3.2.5/dart-io/ProcessInfo/currentRss.html
• https://api.dart.dev/stable/3.2.5/dart-io/ProcessInfo/maxRss.html
• https://api.dart.dev/stable/3.2.5/dart-developer/NativeRuntime/writeHeapSnapshotToFile.html (most likely not available in release mode tho)
• There's also https://github.com/dart-lang/leak_tracker/tree/main/pkgs/memory_usage doing some more

These APIs make it available for Dart and Flutter.

Are you willing to submit a PR?

Yes

One problem with this is, that this is a pretty new API, meaning using it would break for currently supported lower versions.

[buenaflor]

From what I can see I assume currentRss and maxRss are stable enough to use