Move snapshot/restore reference content to elasticsearch reference

[shainaraskas]

Related to #1356

our self-managed repository types (and possibly other pages in the snapshot/restore section) act as reference content and contain client settings for snapshot repositories. we should pull the settings out of the tutorials if we can (without reducing the quality of the tutorial)

example page https://www.elastic.co/docs/deploy-manage/tools/snapshot-and-restore/s3-repository

[yetanothertw]

To follow up on this issue, these three pages follow a similar structure/pattern and all would benefits from individual reference docs:

• S3
• Azure
• GCS repository

Part I would be to merge elastic/elasticsearch#144481 to create the reference docs and part II #5544 would be merged after, so that the that the newly created pages can be leveraged (and linked to).

[yetanothertw]

Hi @DaveCTurner,

I'm working on this issue to refactor some of the S3/Azure/GCS snapshot repo docs.

I've split snapshot repository docs: the long client/repository settings lists for S3, Azure, and GCS now live in dedicated reference pages in the elasticsearch repo (configuration-reference/s3-repository-settings.md, etc.). The deploy-manage pages in docs-content now have short summaries (while also leaving the setup/how-to steps untouched) and links to those references.

If you could please take a look and flag anything that feels off (structure, links, or missing nuance, or anything that should be called out differently), that’d be helpful.

The two PRs are:

• Part I [Docs] Move snapshot/restore reference content to elasticsearch reference elasticsearch#144481
• Part II Move snapshot/restore reference content to reference - part II #5544

Many thanks in advance!

[yetanothertw]

During review, David suggested we also move these settings to the reference for consistency:

• Shared file system repository
• Read-only URL repository
• Source-only repository

So I've expanded the scope of the changes to cover these as well.