feat: add automatic session recovery for streamable http client

[crondinini-ant]

Motivation and Context

Per the MCP spec: "When a client receives HTTP 404 in response to a request containing an Mcp-Session-Id, it MUST start a new session by sending a new InitializeRequest without a session ID attached."

This implements automatic session recovery when the server returns 404 "session not found", reconnecting and retrying the request.

How Has This Been Tested?

Manual tests

Breaking Changes

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation update

Checklist

• I have read the MCP Documentation
• My code follows the repository's style guidelines
• New and existing tests pass locally
• I have added appropriate error handling
• I have added or updated documentation as needed

Additional context

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Latest commit: 7b8c63a

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commit: 7b8c63a