Add three classic CAD measurement commands:
- DIST (DI): two-point pick → distance, angle, delta XYZ
- ID: one-point pick → coordinates
- AREA: multi-point polygon pick (Enter to close) → area + perimeter
New CmdResult::Measurement(String) variant ends active command and
prints result to command line without modifying the document.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Each command implementation is now in the same file as its ribbon
tool definition. Groups moved to a dedicated groups/ toolbar folder.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>