[orx-shapes] Add place function and demo for rectangle placement

Introduce `Rectangle.place` to position rectangles dynamically within bounds using anchor points. Added a demo (`DemoRectanglePlace01`) showcasing a 10x10 grid of rectangles evenly distributed across the canvas.

orx-shapes/src/commonMain/kotlin/primitives/RectanglePlace.kt

@@ -0,0 +1,22 @@
+package org.openrndr.extra.shapes.primitives
+
+import org.openrndr.math.Vector2
+import org.openrndr.shape.Rectangle
+
+/**
+ * Places a given rectangle (`item`) within the bounds of the current rectangle (`this`),
+ * positioning it based on the specified anchor point.
+ *
+ * @param item The rectangle to be placed within the current rectangle.
+ * @param anchor The relative position of the anchor point within the bounds of the current rectangle.
+ *               Defaults to `(0.5, 0.5)` which centers the item within the current rectangle.
+ * @return A new rectangle representing the positioned `item` within the current rectangle.
+ */
+fun Rectangle.place(item: Rectangle, anchor: Vector2 = Vector2(0.5, 0.5), itemAnchor: Vector2 = anchor): Rectangle {
+    return Rectangle(
+        x = x + (width * anchor.x - item.width * itemAnchor.x),
+        y = y + (height * anchor.y - item.height * itemAnchor.y),
+        width = item.width,
+        height = item.height
+    )
+}