Export Additional Metrics to spacelift-promex

We are heavy users of Grafana and Prometheus for observability and alerting. The current metrics that Spacelift exposes to prometheus today is very limiting and we want to build out a rich set of dashboards that give insight into platform performance and also the developer experience.

We noticed that only ~5/36 graphql metrics are being exposed in the spacelift-promex

Asks:

1. Ensure that spacelift-promex is exporting all metrics available in the metrics API

2. Be able to adjust histogram buckets for all relevant metrics