Fix: allow wheel zoom while sprinting (Shift)

The orbit camera suppressed wheel zoom whenever Shift/Ctrl was held, to
reserve Shift/Ctrl+wheel for the paint brush resize. But Shift is also
the sprint key, so sprinting blocked zoom outside paint mode.

Gate the reservation on PanEnabled (set only by PaintMode.Enter/Exit), so
the wheel is only claimed for brush resize while actually in paint mode;
otherwise it zooms normally.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Assets/Scripts/Components/Controller/ThirdPersonOrbitInput.cs

@@ -238,9 +238,11 @@ public class ThirdPersonOrbitInput : MonoBehaviour
 
             float scale = CurrentScale();
 
-            // Shift/Ctrl+wheel is reserved for the paint brush resize (MeshPainter), so the orbit camera
-            // ignores the wheel while either is held - otherwise it would zoom and resize at once.
-            float scroll = (InputUtil.ShiftHeld() || InputUtil.CtrlHeld()) ? 0f : InputUtil.ReadScroll();
+            // Shift/Ctrl+wheel is reserved for the paint brush resize (MeshPainter) - but only in paint
+            // mode (PanEnabled), where the resize actually claims the wheel. Outside paint mode Shift is
+            // the sprint key, so the wheel must still zoom.
+            bool brushResizeClaimsWheel = PanEnabled && (InputUtil.ShiftHeld() || InputUtil.CtrlHeld());
+            float scroll = brushResizeClaimsWheel ? 0f : InputUtil.ReadScroll();
             if (!Mathf.Approximately(scroll, 0f))
             {
                 // One wheel notch = one zoom step (sign only, platform-independent). The step scales with