#39676 refactor: Migrate users.register endpoint to OpenAPI with AJV validation

Proposed changes

Migrates the users.register endpoint from the legacy addRoute() pattern to the new OpenAPI-compatible chained route pattern with inline AJV validation schemas.

Resolves: RocketChat/Rocket.Chat-Open-API#150

Changes

apps/meteor/app/api/server/v1/users.ts

• Replaced legacy API.v1.addRoute('users.register', ...) with the new chained .post('users.register', ...) pattern on the existing usersEndpoints variable
• Added local UserRegisterParamsPOST type, UserRegisterParamsPostSchema, and isUserRegisterParamsPOST validator (moved from rest-typings)
• Added body: isUserRegisterParamsPOST replacing deprecated validateParams
• Added response validation schemas:
  • 200 with $ref: '#/components/schemas/IUser' via Typia
  • 400 with validateBadRequestErrorResponse
• Used async function action() named handler (not arrow function)
• Fixed error handling in validateCustomFields catch block to pass e.message instead of raw error object
• Excluded sensitive fields (services, inviteToken) from the returned user object via projection
• Handled inactiveReason: null from the database by deleting the property when null to satisfy Typia schema validation (same workaround as users.create)
• Business logic, permissions, and side effects are completely unchanged

packages/rest-typings/src/v1/users.ts

• Removed /v1/users.register entry from the UsersEndpoints interface (now auto-generated via ExtractRoutesFromAPI)
• Removed import type { UserRegisterParamsPOST } and its re-export (no longer needed in this file)

packages/rest-typings/src/v1/users/UserRegisterParamsPOST.ts

• Deleted entirely — the AJV schema, compiled validator, and type are now defined locally in the endpoint file

packages/web-ui-registration/src/users-register.d.ts

• Added declare module '@rocket.chat/rest-typings' augmentation to re-expose the users.register endpoint type for the web-ui-registration package, which depends on it for registration form typing

.changeset/migrate-users-register-openapi.md

• Added changeset with minor bump for @rocket.chat/meteor, @rocket.chat/rest-typings, and @rocket.chat/web-ui-registration

Test results

Summary by CodeRabbit

• New Features

  • Added OpenAPI support for the user registration endpoint.

• Refactor

  • Improved registration validation and error messages, with more reliable handling of custom fields and normalization of inactive reason.

• Chores

  • Minor version bumps for registration-related packages.