Add OneOf assert

[josecarlosbrandao]

Add new assert to allow one of constraints (1 exclusive match)

Added this here because https://github.com/uphold/paypal-client/pull/60 required this type of validation to have more readable code

[Copilot]

Pull request overview

Adds a new OneOf assert to the validator.js-asserts package, along with exports, TypeScript typings, and tests to validate behavior.

Changes:

• Added OneOf assert implementation (src/asserts/one-of-assert.js) and exported it from src/index.js.
• Added TypeScript definition for oneOf(...) in src/types/index.d.ts.
• Updated test suite to include OneOf in the export list and added dedicated OneOf tests.

Reviewed changes

Copilot reviewed 4 out of 5 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
test/index.test.js	Updates the expected exported assert count and list to include OneOf.
test/asserts/one-of-assert.test.js	Adds unit tests covering OneOf validation and violation aggregation behavior.
src/types/index.d.ts	Adds the oneOf(...constraintSets) TypeScript API definition.
src/index.js	Exports the new OneOf assert from the package entry point.
src/asserts/one-of-assert.js	Implements OneOf validation against multiple constraint sets using validator.js constraints.

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