User name, id and email should be included in OTel export

[mmarczell-graphisoft]

SDK Feature Request

Describe the problem you’re trying to solve
If I use Embrace.setUserEmail(), Embrace.setUserIdentifier(), Embrace.setUsername() functions, and add my own OpenTelemetry exporters to the SDK, I would like the user values I set to be included in the OpenTelemetry logs.

Describe alternatives you’ve considered or workarounds you’re using
There might be a call on the SDK interface that lets me add custom properties to every log globally...?

Additional context
I'm not yet sure whether these values should be sent as standard OTel attributes user.id, user.name and user.email because those attributes are marked as "development" in the OTel docs, or use custom names such as emb.user.*.

If the SDK will send these with custom names, I would like it to be consistent with those used in the iOS SDK when the same feature is implemented there, see embrace-io/embrace-apple-sdk#489 (because as far as I can tell, in the Android SDK they are currently named io.embrace.* internally).

[bidetofevil]

Thanks for the report. We should do this - we just need to figure out what it looks like

[bidetofevil]

The current thinking is adding the only non-deprecated attribute, userId, into all exported telemetry as an attributed using the attribute defined in the OTel semantic conventions (user.id). The other ones are deprecated because they contain PII so we don't encourage their use in telemetry. If you really need them and are OK with recording PII, you can use a session property to do so, and they'll been included in the exported spans and logs.