Implement node-reset before unregister

[bouwew]

Implement both node-removal and node-resetting as in Source.

Summary by CodeRabbit

• New Features

  • Public API to unregister/remove a node by MAC added.

• Improvements

  • Node removal now resets the device and clears its cache automatically.
  • Node reset acknowledgments are handled explicitly for clearer feedback.
  • Early MAC validation surfaces invalid-address errors sooner.

• Tests

  • Expanded test coverage for node reset and removal flows.

• Documentation

  • Changelog updated.

• Chores

  • Version bumped to 0.46.1a1.