fix(mcp-tools): restore MCP tools listing by removing oneOf from search_items schema and standardizing tool names to snake_case; align item_type param.\n\n- Simplify search_items inputSchema to a single object (string-only params) to avoid client schema rejection\n- Rename workflow tools in config to snake_case to match SDK handlers\n- Expose item_type consistently to match server handler signature\n\nValidated by: handle_list_tools() returns 27 tools incl. search_items; handle_call_tool('server_health', ...) returns healthy JSON

Author: Peter