Split large plugin reference docs into multiple pages

## Definition of done
Decide how to handle plugin reference docs with a lot of content that become hard to navigate (AI Proxy or OpenTelemetry for example).

## Size
M/L

Review the plugin reference documentation, using AI Proxy and OpenTelemetry as examples of pages with a lot of content. Decide how these references should be split into multiple pages and document a clear approach; done means the handling strategy is defined for the affected references.

Written by the indexing model from the issue text.