Expand Conversation API

[bibryam]

We need Java SDK to support Conversation API, including the latest changes:

• [ ] Promotion of the Conversation API from alpha to beta (#8784).
• [ ] - Addition of streaming response support (dapr issue #8813).
• [ ] - Implementation of tool calling support (#8816).

Acceptance Criteria

• SDK supports the beta version of the Conversation API.
• SDK includes support for streaming responses.
• SDK includes support for tool calling.
• SDK examples including the new API capabilities.
• Quickstarts updated to include SDK example