[REQUEST]: Managed Input pages should not be under the Opentelemetry section

### Description

Currently the managed inputs are all under: https://www.elastic.co/docs/reference/opentelemetry/managed-inputs

We have been adding inputs in to the managed inputs infrastructure which are not solely in the OTEL domain (promethues, _bulk and others). Let's rethink how managed inputs can have their own more prominent place in the docs.

### Resources

https://www.elastic.co/docs/reference/opentelemetry/managed-inputs

### Collaboration

TBD. The docs and product team will work together to determine the best path forward.

### Point of contact.

**Main contact:** @perk

**Stakeholders:**
@ishleenk17 @nimarezainia

Start by reviewing the current managed-inputs page at https://www.elastic.co/docs/reference/opentelemetry/managed-inputs and the issue's examples of inputs outside the OTEL domain. Coordinate with @perk and the listed docs and product stakeholders to determine the new information architecture. Done means managed inputs have a more prominent location that is not confined to the OpenTelemetry section.

Written by the indexing model from the issue text.