ExposeScope/McpTransport gain as_str/parse (privacy-safe fallback: an
unparsed scope becomes None, not All/Selected) so commands.rs can read
them out of Settings' string fields. Declares the mcp submodules
(scope always compiled; handler/http_transport/server/stdio_transport/
token behind the `mcp` cargo feature) and removes the todo!() RmcpServer
stub -- its real implementation moves to mcp::server in the next commits.
iamdoubz
c73245f293