Changes:
* Moves `Retrieve selected fields` to its own page and adds a title abbreviation.
* Adds existing script and stored fields content to `Retrieve selected fields`
* Adds a xref for `Retrieve selected fields` to `Search your data`
* Adds related redirects and updates existing xrefs
This feature adds a new `fields` parameter to the search request, which
consults both the document `_source` and the mappings to fetch fields in a
consistent way. The PR merges the `field-retrieval` feature branch.
Addresses #49028 and #55363.
Changes:
* Condenses and relocates the `docvalue_fields` example to the 'Run a search'
page.
* Adds docs for the `docvalue_fields` request body parameter.
* Updates several related xrefs.
Co-authored-by: debadair <debadair@elastic.co>
Moves the source filtering example snippets form the "Request body
search" API docs page to the "Return fields in a search" section of the
"Run a search" page.
This PR adds a section to the new 'run a search' reference that explains
the options for returning fields. Previously each option was only listed as a
separate request parameter and it was hard to know what was available.
James Rodewig
Julie Tibshirani
James Rodewig