fix: ensure custom headers are included in initial SSE connection to remote MCP Server#46

hashemix merged 3 commits intomainrust-mcp-stack/rust-mcp-sdk:mainfrom

fix/issue-45-custom-headers-ignored-on-sse-connection-requestrust-mcp-stack/rust-mcp-sdk:fix/issue-45-custom-headers-ignored-on-sse-connection-requestCopy head branch name to clipboard