Allow users mirroring what they are placing to simplify duplication logic
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Maintainer triage (2026-01-15)
Order: 8/16
Impact: Medium
Estimate: M/L
Tags: priority:P1, tools, geometry
Summary: Add mirroring (symmetry) while duplicating/moving/placing for faster ship layout iteration.
Notes:
  • Depends on having copy/paste/duplicate and selection transforms first.
  • For tile-layout structures, mirroring needs to correctly transform positions and rotations (and handle asymmetric layouts).