Add help text for runtime fields source.

[lockewritesdocs]

Summary

Adds (or tries to) help text to the source field for runtime fields, introduced in #84184.

Accessing the changes

1. Navigate to Index Management.
2. Choose Index Templates and define an index template.
3. Under Mapping, choose Runtime fields.

The text should display under the script field (it doesn't).

Checklist

Delete any items that are not applicable to this PR.

• [ x ] Any text added follows EUI's writing guidelines, uses sentence case text and includes i18n support

[elasticmachine]

Pinging @elastic/es-ui (Team:Elasticsearch UI)

[alisonelizabeth]

@lockewritesdocs I updated your PR so that the help text displays now. Let me know if you think it is OK as-is, or if you prefer to have the text and link separate in a two-column layout (the text is a little long so it felt weird when I initially had it that way).

[lockewritesdocs]

Thanks for the assist @alisonelizabeth! I made some minor text changes and also defined an EuiCode element for _source. Built and tested locally without errors, so 🤞

[alisonelizabeth]

Change LGTM. Tested locally. Thanks for working on this @lockewritesdocs!

[alisonelizabeth]

Note: I added the 8.0.0 tag and changed release_note:enhancement to release_note:skip, since this is just a docs change and I believe there is already a release note for the overall runtime fields feature.

[kibanamachine]

💚 Build Succeeded

• continuous-integration/kibana-ci/pull-request
• Commit: 2d9e209

Metrics [docs]

Distributable file count

id	before	after	diff
default	46933	47693	+760

Page load bundle

Size of the bundles that are downloaded on every page load. Target size is below 100kb

id	before	after	diff
runtimeFields	30.9KB	31.3KB	+446.0B

History

• 💚 Build #92606 succeeded 05605de
• 💚 Build #92547 succeeded ec343c8

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@elasticmachine merge upstream