Add support for protocol version 2025 06 18 (#54) * Add basic support for 2025-06-18 header * Remove json-rpc batch support * Extend _meta and ajson slash in key support * Add title to more entries * Annotations, meta, output schema, structured outpu * Update documentation for 2025-06-18 * Update demos * Update changelog

Merge branch 'main' of https://github.com/abap-ai/mcp 

5 full testsuite for the mcp server (#6) * Add testsuite with MCP typescript SDK

Simplifications to support downport