Sentry Structured Logging for Elixir

[AbhiPrasad]

Problem Statement

https://develop.sentry.dev/sdk/telemetry/logs/

Sentry is adding support for structured logging. Let's add it to the Elixir SDK!

Solution Brainstorm

1. Define the logs protocol and log envelope item in the SDK
2. Add the Public API (SDK options and methods) as per the docs
3. Make sure the the SDK follow the documented behavior
4. Attach default attributes to the SDK as per docs
5. Add logging integrations. We should support both Elixir Logger and erlangs's :logger. With Elixir Logger we should also make sure to add all the metadata directly as log attributes. We should sync about attribute naming before fully implementing.
6. Create a GH discussion that contains instructions for setting up the SDK in your repo. Eventually this will be moved into the primary docs. See the JS SDK's GH discussion for inspiration.

[solnic]

Gonna do it once I'm done with logging in the Ruby SDK 😄