sysutils/geomman: Interactive GEOM Manager

geomman is a text-based disk management tool for FreeBSD,
built on top of bsddialog(3). It provides a simple TUI
for working with partitions, filesystems, and GEOM labels.

This is brauliorivas' GSoC 2025 project, to be eventually
included into base.

Sponsored by: Google LLC (GSoC 2025)