Support OpenTelemetry events

[danelson]

Is your feature request related to a problem? Please describe.
OpenTelemetry supports "Events" which are essentially LogRecordss with an additional EventName field. This field is not visible when sending logs to Loki over OTLP.

Using the example payload from https://github.com/open-telemetry/opentelemetry-proto/blob/main/examples/events.json (changing timestamp). Observe that browser.page_view is not visible.

Describe the solution you'd like
At a minimum I would like the EventName to be visible and searchable. I am not sure how it should map to Loki, e.g. label or structured metadata.

Describe alternatives you've considered
None

Additional context

• https://opentelemetry.io/docs/specs/semconv/general/events/
• https://github.com/open-telemetry/opentelemetry-specification/blob/v1.48.0/specification/logs/data-model.md#field-eventname