package:dart_mcp v0.2.1

• Fix the protocolLogSink support when using MCPClient.connectStdioServer.
• Update workflow example to show thinking spinner and input and output token
  usage.
• Update file system example to support relative paths.
• Fix a bug in notification handling where leaving off the parameters caused a
  type exception.
• Added --help, --log, and --model flags to the workflow example.
• Fixed a bug where the examples would only connect to a server with the latest
  protocol version.
• Handle failed calls to listRoots in the RootsTrackingSupport mixin more
  gracefully. Previously this would leave the roots future hanging
  indefinitely, but now it will log an error and set the roots to empty.
• Added validation for Schema extension.
• Fixed an issue where getting the type of a Schema with a null type would
  throw.