New input documentation

[cloudcannon]

DO NOT MERGE until after input validation and updated URL inputs go to main

[Copilot]

Pull Request Overview

This PR introduces dedicated “what is” documentation for each input type, updates existing guides and changelogs to point to those new pages, and enhances the CloudCannon configuration with input validation, a new reference collection, and commit template requirements.

• Added new MDX articles under articles/ (e.g., what-is-a-*) for each input type.
• Updated all existing guides, changelogs, and references to use the new documentation paths.
• Extended cloudcannon.config.cjs with:
  • A Date input icon
  • An _inputs block to require title on article-instructions
  • A new reference collection schema
  • Enhanced commit_templates schema with required message input

Reviewed Changes

Copilot reviewed 187 out of 191 changed files in this pull request and generated no comments.

File	Description
guides/unified-configuration-migration-guide/input-configuration.mdx	Updated Select input link to new “what-is” docs
cloudcannon.config.cjs	Added Date icon, _inputs validation, new reference schema, commit templates
articles/what-is-*.mdx (many files)	New standalone articles for each input type

Comments suppressed due to low confidence (2)

guides/unified-configuration-migration-guide/input-configuration.mdx:25

• The anchor #options may not exist in the new what-is-a-select-input page—verify that the header in that doc is exactly Options so the fragment link resolves correctly.

Before Unified Configuration, CloudCannon could use build data to populate the <a href="/documentation/articles/what-is-a-select-input/#options" target="_blank" rel="noopener">Select and Multiselect input</a> option `value_key` values. As a successful build is no longer required to edit your files, you must define all values for the `value_key` option in the configuration cascade rather than use values generated by a build integration.

cloudcannon.config.cjs:241

• The _inputs entry for "$.title" specifies options but omits a type (e.g. type: text). Without a type, CloudCannon may not recognize the input configuration—add type alongside options.

      _inputs: {