OpenAPI Generator - generate clients and servers from OpenAPI specs
USE WHEN: user mentions "OpenAPI Generator CLI", "generate Java client", "generate Spring server",
"openapi-generator-cli", "openapi-generator-maven-plugin", asks about "generate server from OpenAPI",
"OpenAPI Generator templates"
DO NOT USE FOR: TypeScript-only generation - use `openapi-codegen` instead;
Writing OpenAPI specs - use `openapi` instead; GraphQL - use `graphql-codegen` instead