Update README.md

Author: hossain-khan

README.md

@@ -1,6 +1,9 @@
 # json5-kotlin
 JSON5 implementation for Kotlin/JVM
 
+> [!WARNING]  
+> This is an experimental project. It's non-functional at the moment.
+
 This project uses [Gradle](https://gradle.org/).
 To build and run the application, use the *Gradle* tool window by clicking the Gradle icon in the right-hand toolbar,
 or run it directly from the terminal:
@@ -21,4 +24,4 @@ This project follows the suggested multi-module setup and consists of the `app`
 The shared build logic was extracted to a convention plugin located in `buildSrc`.
 
 This project uses a version catalog (see `gradle/libs.versions.toml`) to declare and version dependencies
-and both a build cache and a configuration cache (see `gradle.properties`).
+and both a build cache and a configuration cache (see `gradle.properties`).