fix: Fix offset reset issue caused by floating-point precision at boundary positions

When the panel is already at a boundary position, floating-point precision
errors on some devices can cause unexpected offset resets in the position
calculation.

By applying floor() to the position calculations for top, left, bottom, and
right edges in FloatingPanelLayoutAnchor, we ensure integer values are
returned, preventing layout issues caused by floating-point precision errors.

Author: 0x1306a94

Sources/Layout.swift

@@ -374,13 +374,13 @@ class LayoutAdapter {
             let diff = anchor.isAbsolute ? anchor.inset : position.mainDimension(referenceBounds.size) * anchor.inset
             switch anchor.referenceEdge {
             case .top:
-                return referenceBounds.minY + diff
+                return floor(referenceBounds.minY + diff)
             case .left:
-                return referenceBounds.minX + diff
+                return floor(referenceBounds.minX + diff)
             case .bottom:
-                return referenceBounds.maxY - diff
+                return floor(referenceBounds.maxY - diff)
             case .right:
-                return referenceBounds.maxX - diff
+                return floor(referenceBounds.maxX - diff)
             }
         default:
             fatalError("Unsupported a FloatingPanelLayoutAnchoring object")