According to [the MCP spec](https://modelcontextprotocol.io/specification/2025-03-26/basic/lifecycle#version-negotiation):

> If the server supports the requested protocol version, it MUST respond with
> the same version. Otherwise, the server MUST respond with another protocol
> version it supports.

This adds `mcp.ValidProtocolVersions`, a slice with all currently specified MCP
versions.

In the `server` package we check if the client provided a known MCP version
and, if so, return that version. Otherwise `LATEST_PROTOCOL_VERSION` is
returned as previously.

fix: panic when streamable HTTP server sends notification

Closes #343

* fix(server): resolve stdio server context cancellation bug

Fix a critical bug in the stdio server's readNextLine function that was
causing "Error reading input" and "context cancelled" errors when Claude
Desktop attempted to connect to MCP servers.

The issue was in the select-default pattern that would immediately bypass
context cancellation checks and proceed with blocking ReadString operations
even when the context was cancelled. This prevented proper cleanup and
caused connection failures.

Changes:
- Remove problematic select-default pattern in readNextLine goroutine
- Simplify the read logic to directly call reader.ReadString('\n')
- Maintain proper done channel handling for result communication
- Ensure context cancellation is respected throughout the read operation

This resolves connection issues introduced in version 0.30.0 where the
stdio transport became unreliable for client connections.

Fixes: stdio server connection failures with Claude Desktop

* refactor: remove redudant signaling channels

---------

Co-authored-by: Marcos <marcos@atani.com>

…ce (#347)

* Add WithStreamableHTTPServer option to StreamableHTTPServer to allow setting a custom HTTP server instance, similar to existing functionality in SSE.

* Add better documentation notes to WithHTTPServer and WithStreamableHTTPServer

---------

Co-authored-by: Yashwanth H L <yashwanth_hl@intuit.com>

* fix(Srv/stream): add ID field to PingRequest

* fix: make session requestID unique and incremental