Restore /guide navigation experience in ES reference section

[szabosteve]

Overview

Related to #1644

Description

We have received feedback that the new goal-based structure makes it difficult for users who are accustomed to the /guide product-based navigation.

The reorganization around user tasks rather than products has disrupted how many users search for and consume documentation.

For example, users managing specific clusters or studying for certifications struggle to find the right documentation.

Solution

Restore a familiar experience by replicating the elastic.co/guide/index.html structure at elastic.co/docs/reference, mirroring the navigation used in versions 8.18 and earlier.

Proposed tasks for Elasticsearch

• Create a dedicated Elastic APIs page

• Pull the following into Elasticsearch:

  • Text analysis: Built in analyzer, Tokenizer, Token filter, Characters filter, Normalizers
  • Ingest processor
  • Aggregations

• Create a new Machine learning page and pull in the following:

  • Supplied configurations
  • Analysis functions

• Reorganize the ES reference landing page to replicate the /guide docs landing page

• Reorganize the Reference landing page to replicate the /guide docs landing page

[leemthompo]

Update: all of the navigation updates are complete

Remaining item: refactor the landing page which I suggest we handle as a batch together with ES solution landing page and the main docs landing page

Might make sense to roll those up into a new initiative?

[leemthompo]

closing this as the navigation part is complete