Show live row, column and span while dragging controls in the Web designer

In the Web project page designer, dragging or resizing a control gives no numeric feedback until the mouse is released: the Row, Column, and span values only appear in the Inspector after the drop. The desktop window designer, by contrast, shows a live measurement readout during drag gestures, and updates its position/size fields in realtime while resizing.

Add a live on-canvas readout in grid terms during move and resize gestures in the Web page designer — for example Row 4, Column 2 · Span 6 × 1 — reflecting the placement the control will actually occupy, including collision resolution, so controls can be positioned precisely in the responsive grid. The readout is toggled by a designer toolbar button, mirroring the desktop designer's measurements toggle.