add poc note

Author: lstreckeisen

README.md

@@ -1,9 +1,12 @@
 ![Context Mapper](https://raw.githubusercontent.com/wiki/ContextMapper/context-mapper-dsl/logo/cm-logo-github-small.png)
-# ContextMapper DSL Language Server
-[ContextMapper](https://contextmapper.org/) is an open source tool providing a Domain-specific Language based on Domain-Driven Design (DDD) patterns for context mapping and service decomposition.
+# Context Mapper DSL Language Server
+
+> **_NOTE:_** This language server is a proof of concept and does not support all Context Mapper features yet.
+
+[Context Mapper](https://contextmapper.org/) is an open source tool providing a Domain-specific Language based on Domain-Driven Design (DDD) patterns for context mapping and service decomposition.
 
 ## System Requirements
-The ContextMapper language server is implemented with Langium. To run the language server the following tools have to be installed locally:
+The Context Mapper language server is implemented with Langium. To run the language server the following tools have to be installed locally:
 * [Node.js](https://nodejs.org/en/download) (v22)
 
 ## Build and/or Run the language server