v0.21.1

Fixed

• hermes_cli/main.py: added the daemon subcommand (registered in
  0.21.0's warm-daemon port) to _BUILTIN_SUBCOMMANDS. Without it, hermes daemon was paying the eager plugin-discovery cost on every invocation
  instead of taking the fast path every other built-in subcommand gets.
  Caught by test_startup_plugin_gating.py::test_builtin_set_covers_every_registered_subcommand.