D3 Estimate Axis Text + Tick Buffers
This example measures and displays the pixel width required by a D3 axis, including its tick marks and tick text labels. It uses a categorical axis with three names, 'bob', 'billy', and 'bobicus', rendered as an SVG via `d3.axisLeft` and an ordinal scale. The code calculates the buffer space needed for these elements, providing a practical reference for layout when positioning additional chart components beside an axis. The implementation uses D3 v7 and appends the axis to an SVG canvas sized to the browser window.