adding some instructions to the readme

Author: Petermarcu

readme.md

@@ -12,12 +12,15 @@ The server is implemented in as much of an API-first way as possible. To start t
 
 Interesting features:
 
-- TypeSpec, generating both JSON Schema and OpenAPI3.
+- TypeSpec, generating JSON Schema, OpenAPI3, and clients in multiple languages.
 - Docs are exposed under the `/docs` endpoint.
 - TypeScript types are generated from JSON Schema using `json-schema-to-typescript`.
 - Routes are attached and requests/responses are validated based on the OpenAPI using `fastify-openapi-glue`.
 
 ## Prerequisites
 
 1. Install [node](https://nodejs.org).
-2. For Python codegen, install [Python](https://python.org) and [pip](https://pip.pypa.io/en/stable/installation/).
+2. Install [TypeSpec](https://typespec.io) `npm install -g @typespec/compiler`
+3. For Python codegen, install [Python](https://python.org) and [pip](https://pip.pypa.io/en/stable/installation/).
+4. For Java codegen, install the [JDK](https://www.oracle.com/java/technologies/downloads/#java17) 17 or higher.
+5. For CSharp codegen, install the [.NET SDK](https://dotnet.microsoft.com/en-us/download) version 8 or higher.