Add product telemetry for HTTP JSON streaming endpoint

[VineethReddy02]

Is your feature request related to a problem? Please describe.

The request is specific to call home telemetry for the JSON streaming endpoint. Today in the telemetry we cannot distinguish/find the total number of samples ingested by JSON vs Prometheus remote-write endpoint.

Ask 1: Product telemetry:

The feature request is to add a new telemetry data point representing the total number of samples ingested by the JSON streaming endpoint i.e. promscale_json_ingested_samples_total.

Ask 2: Prometheus metrics:

Add this to exposed Prometheus metrics as well for dashboarding and debugging purposes by adding a new label matcher i.e. endoint: json to existing Prometheus metric promscale_ingest_inserted_total{kind="sample",type="metric"}.

Describe the solution you'd like. New telemetry data point representing the use of JSON endpoint by measuring the total number of samples ingested.

Describe alternatives you've considered nil.

How would this feature help you* To gauge product adoption for custom metrics.

Additional context Currently, we use promscale_ingested_samples_total to measure the total samples that are ingested by a specific Promscale instance. But this calculates the sum of Prometheus remote-write and JSON endpoint. Finding the usage of only JSON streaming endpoint is a blindspot. Supporting a new metric in call home telemetry will add visibility to this feature.