Metrics: add attributes and switch to snake_case

[martin-majlis-s1]

Jira Link: https://sentinelone.atlassian.net/browse/DSET-4558

🥅 Goal

I have received feedback in the PR in the Otel Contrib - open-telemetry/opentelemetry-collector-contrib#29446 (comment) that:

• metric names should be snake_case
• there should be support for attributes

🛠️ Solution

I have renamed the metrics as well as introduced possibility to pass the processing entities as well as name.

🏫 Testing

Same as in the PR #61

But add more dataset exporters in the demo repository - src/otelcollector/otelcol-config.yml

service:
  pipelines:
    traces:
      receivers: [otlp]
      processors: [batch, attributes]
      exporters: [otlp, debug, spanmetrics, dataset, dataset/aaa, dataset/bbb, dataset/ccc, dataset/ddd]
    metrics:
      receivers: [httpcheck/frontendproxy, otlp, spanmetrics, prometheus]
      processors: [filter/ottl, transform, batch]
      exporters: [otlphttp/prometheus, debug]
    logs:
      receivers: [otlp]
      processors: [batch, attributes]
      exporters: [otlp/logs, debug, dataset, dataset/aaa, dataset/bbb, dataset/ccc, dataset/ddd]

We can see, that metrics are now snake_case:

And it's possible to separate metrics based on entity (logs/traces) and name:

[tomaz-s1]

LGTM, thanks for addressing the upstream feedback.