Remove unused UnitMode enum

The enum was defined but never used in the implementation.
Using int constants k_mode_type_hold and k_mode_type_guard instead
for consistency with the draw command structure.

Co-authored-by: djeada <[email protected]>

render/geom/mode_indicator.h

@@ -5,8 +5,6 @@
 
 namespace Render::Geom {
 
-enum class UnitMode { Hold, Guard };
-
 // Mode type constants for rendering
 constexpr int k_mode_type_hold = 0;
 constexpr int k_mode_type_guard = 1;