Defense draws every rotation half a turn round, so feeding that to the
glyph flipped every icon nobody had turned. An icon stored at 0 now stays
upright on both sides; a turned icon stores 2pi for a full turn, never 0,
and points along the map. Stepping starts from the angle on screen, and
page transitions use the same rule and turn icons the short way.

A held mouse button means a drag or a rotation handle is mid-edit and will
commit its own angle on release, so X does nothing until it's let go.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>