Add documentation for pattern_text mapping type

[parkertimmins]

Add docs for the pattern_text mapping type.

Fixes #135030

[elasticsearchmachine]

Pinging @elastic/es-storage-engine (Team:StorageEngine)

[elasticsearchmachine]

Pinging @elastic/core-docs (Team:Docs)

[github-actions]

🔍 Preview links for changed docs

• docs/reference/elasticsearch/mapping-reference/match-only-text.md
• docs/reference/elasticsearch/mapping-reference/pattern-text.md
• docs/reference/elasticsearch/mapping-reference/text-type-family.md
• docs/reference/elasticsearch/mapping-reference/field-data-types.md
• docs/reference/elasticsearch/mapping-reference/text.md
• docs/reference/elasticsearch/rest-apis/highlighting-settings.md

[github-actions]

ℹ️ Important: Docs version tagging

👋 Thanks for updating the docs! Just a friendly reminder that our docs are now cumulative. This means all 9.x versions are documented on the same page and published off of the main branch, instead of creating separate pages for each minor version.

We use applies_to tags to mark version-specific features and changes.

Expand for a quick overview

When to use applies_to tags:

✅ At the page level to indicate which products/deployments the content applies to (mandatory)
✅ When features change state (e.g. preview, ga) in a specific version
✅ When availability differs across deployments and environments

What NOT to do:

❌ Don't remove or replace information that applies to an older version
❌ Don't add new information that applies to a specific version without an applies_to tag
❌ Don't forget that applies_to tags can be used at the page, section, and inline level

🤔 Need help?

• Check out the cumulative docs guidelines
• Reach out in the #docs Slack channel

[jordan-powers]

This could use some clarification--which is better for log messages, match_only_text or pattern_text?

[martijnvg]

LGTM, I think someone from the docs team should also take a look at this.

[leemthompo]

I just noticed a few things, docs wise, as I drove by, reviewing the URL preview . Let me know if anything is unclear :)

[leemthompo]

I wonder if we should consider splitting these pages up for readability, if you're game go ahead, otherwise could create an issue to do this in a follow-up. We'd need to ensure redirects are set up in /docs/redirects.yml.

• Text family overview
  • text field type
  • match_only_text
  • pattern_text

[leemthompo]

Thanks for jumping on the page splitting @parkertimmins!

I think you need something like the following redirect pattern in https://github.com/elastic/elasticsearch/blob/main/docs/redirects.yml to fix the error:

'reference/elasticsearch/mapping-reference/text.md':
  anchors:
    'match-only-text-field-type': 'reference/elasticsearch/mapping-reference/match-only-text.md#match-only-text-field-type'
    'match-only-text-params': 'reference/elasticsearch/mapping-reference/match-only-text.md#match-only-text-params'

Beware the syntax can be kinda finicky :)

Note: You need these because the link failures are X-links from the docs-content repo

[parkertimmins]

@jordan-powers and @martijnvg What do ya'll think of this blurb? I'm having trouble coming up with a description that is succinct and described the difference between pattern_text and match_only_text.