Support "Streamable HTTP" transport

[taobaorun]

(Original content)
Expected Behavior

The "Streamable HTTP" transport is a fantastic feature, particularly beneficial for stateless MCP servers and remote MCP servers in distributed scenarios. It enables MCP to be swiftly employed in production-grade agent applications

Current Behavior

The issue with the current session is that it needs to support distributed sessions.

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(Edit by @chemicL follows)

To split the task, what needs to happen to consider it done:

Steps

• Reviewing the Spec and introducing architectural changes required for the client side aiming for backwards compatibility if possible (WebClient Streamable HTTP support #292)
• Implementing JDK HTTP Client support (feat: implement HttpClient Streamable HTTP transport #337)
• Implementing WebClient Client support (WebClient Streamable HTTP support #292)
• Reviewing the Spec and introducing architectural changes required for the server side aiming for backwards compatibility if possible and allowing both stateful and stateless servers (Streamable HTTP Server abstractions and WebFlux transport provider #420)
• Implementing Servlet Server support (HttpServlet Streamable HTTP server implementation #290)
• Implementing Spring WebMVC Server support (feat: Add Spring WebMVC streamable server transport provider #425)
• Implementing Spring WebFlux Server support (Streamable HTTP Server abstractions and WebFlux transport provider #420)
• Servlet & MVC Stateless: (feat: add WebMVC and HttpServlet stateless server transports #432)

[hongling-dev]

When is 2025-03-26 Implementation 's release date? thx @chemicL

[dyrnq]

stare

[Pratiush]

I would love to contribute on this feature.

[chemicL]

I started diving into the subject and began prototyping it. If there arise some areas where contributions will be useful, I will update this issue with links to individual tasks. Thanks for your patience.

[chemicL]

Folks, feel free to test locally the work in progress in #292 and please report any issues. We will follow up with the JDK HttpClient implementation and then take care of the server side.