Release 0.6.0

In this release, I am moving into a new approach of re-using any existing SDK to implement a client for any provider. This was not possible in the past (some of the clients were not available). This means ApiClient will only be implemented for those providers without a SDK and endpoints are no longer required to return an instance of ApiClient; each endpoint might return a specific client (based on the provided SDK) to deal with the underlining REST API.

• First release published on Maven Central.
• Added an implementation of ReAct (Reason &P Act) agent under examples. This is working but still work in progress.
• Migrating from custom OkHttp-based OpenAiClient to OpenAIClient from official OpenAI Java SDK.
• Create a separate library to handle Hugging Face API.
• Added EndpointException and its subclasses to help handle errors more uniformly, independent from the underlying API. Now all calls to services throw this exception.
• Updated OpenAI model list.
• Greatly improved JsonSchema to support using JSON schemas when defining model output or tool call parameters.
• Reworked Capability to simplify handling of Tools.
• EmbeddingService.get/setDefaultTextTokens() is now get/setDefaultChunkTokens().
• getDefaultReq() in services is now getDefaultRequest().
• ImageGenerationService now returns a List<FilePart> to allow returning image URLs in addition to binary data.
• Removed QuestionAnsweringService and QuestionExtractionService.
• Reworked tests.