RouterBase Java Client 0.1.1

Adds JitPack build configuration so the Java client builds with JDK 17.\n\nLinks:\n- RouterBase: https://routerbase.com\n- Docs: https://docs.routerbase.com/

RouterBase Java Client 0.1.0

Initial Java client release for RouterBase.\n\nIncludes:\n- Maven-ready package metadata for com.routerbase:routerbase-client.\n- Java 11-compatible client for chat completions and model listing.\n- Jackson-based JSON mapping.\n- JUnit tests with fake transport.\n- GitHub Actions CI running Maven verify.\n\nDocs: https://docs.routerbase.com/