fix: add missing items field to UserSchemaAttribute

[sagar-okta]

PR Checklist

• The commit message follows our guidelines
• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)

PR Type

• Bugfix
• Feature
• Code style update (formatting, local variables)
• Refactoring (no functional changes, no api changes)
• Adding Tests
• Build related changes
• CI related changes
• Documentation changes
• Other...

What is the current behavior?

Issue Number: #480

When calling schemaApi.updateApplicationUserProfile with a custom attribute of type: 'array', the SDK strips the items field from the request body. The Okta API then rejects the request with:

Items not present for array property: <prop_name>

Root cause: The items property was accidentally dropped from the UserSchemaAttribute schema when the OpenAPI spec was updated from v4.0.0 to v5.x. The UserSchemaAttributeItems class and the GroupSchemaAttribute.items field were both retained, but UserSchemaAttribute.items was not regenerated.

What is the new behavior?

• UserSchemaAttribute now includes the items field typed as UserSchemaAttributeItems, consistent with GroupSchemaAttribute.
• Callers can pass items: { type: 'string' } (or any valid UserSchemaAttributeItems value) when setting type: 'array' on a custom attribute.
• No behaviour change for attributes that do not use type: 'array'.

Does this PR introduce a breaking change?

• Yes
• No

Other information

Files changed:

• oas-spec/management.yaml — added items field ($ref: UserSchemaAttributeItems, nullable: true) to UserSchemaAttribute schema
• src/generated/models/UserSchemaAttribute.js — added items entry to attributeTypeMap
• src/types/generated/models/UserSchemaAttribute.d.ts — added UserSchemaAttributeItems import and items property declaration

[aniket-okta]

Security audit, type check, unit + jest tests (114/114), and live API smoke test passed. The items field addition is correct and exactly mirrors the GroupSchemaAttribute pattern.