Function wrapText

src/utils/shareUtils.ts:72–97

(
  ctx: CanvasRenderingContext2D,
  text: string,
  x: number,
  y: number,
  maxWidth: number,
  lineHeight: number
)

// 绘制文字（自动换行）
function wrapText(
  ctx: CanvasRenderingContext2D,
  text: string,
  x: number,
  y: number,
  maxWidth: number,
  lineHeight: number
): number {
  const chars = text.split('')
  let line = ''
  let currentY = y

  for (let i = 0; i < chars.length; i++) {
    const testLine = line + chars[i]
    const metrics = ctx.measureText(testLine)
    if (metrics.width > maxWidth && i > 0) {
      ctx.fillText(line, x, currentY)
      line = chars[i]
      currentY += lineHeight
    } else {
      line = testLine
    }
  }
  ctx.fillText(line, x, currentY)
  return currentY + lineHeight
}

// 绘制标签
function drawTag(ctx: CanvasRenderingContext2D, text: string, x: number, y: number, bgColor: string, textColor: string) {