初始提交：三玩法 Web 原型与设计文档

- 玩法一 数字一笔：规则库、求解器、26 关、竖屏触摸 Web 原型、测试
- 玩法二 连连气球：连消畅玩版核心、Web 原型、Cocos 球槽组件与导出脚本
- 玩法三 六边一笔：规则库、求解器、10 关 + 转墙实验包、Web 原型、测试
- 产品文档、UI 设计规范、各玩法 GDD / HANDOFF
- 文档移除全部外部参考作引用；删除玩法二 v0 旧稿

modes/03-hex-walls/web/canvas-painter.ts

@@ -0,0 +1,80 @@
+// Painter 的 Canvas 2D 实现。Cocos 版本换成 Graphics + Label 即可，HexBoardView 不用改。
+import type { Point } from '../src/geom';
+import type { Painter } from '../src/painter';
+
+export class CanvasPainter implements Painter {
+  private readonly ctx: CanvasRenderingContext2D;
+  private readonly fontFamily =
+    '"SF Pro Rounded", "PingFang SC", "Helvetica Neue", "Segoe UI", system-ui, -apple-system, sans-serif';
+
+  constructor(ctx: CanvasRenderingContext2D) {
+    this.ctx = ctx;
+  }
+
+  private path(pts: Point[]): void {
+    const ctx = this.ctx;
+    ctx.beginPath();
+    ctx.moveTo(pts[0].x, pts[0].y);
+    for (let i = 1; i < pts.length; i++) ctx.lineTo(pts[i].x, pts[i].y);
+    ctx.closePath();
+  }
+
+  fillPolygon(pts: Point[], color: string, alpha = 1): void {
+    if (alpha <= 0 || pts.length < 3) return;
+    const ctx = this.ctx;
+    ctx.globalAlpha = alpha;
+    ctx.fillStyle = color;
+    this.path(pts);
+    ctx.fill();
+    ctx.globalAlpha = 1;
+  }
+
+  strokePolygon(pts: Point[], color: string, lineWidth: number, alpha = 1): void {
+    if (alpha <= 0 || pts.length < 2) return;
+    const ctx = this.ctx;
+    ctx.globalAlpha = alpha;
+    ctx.strokeStyle = color;
+    ctx.lineWidth = lineWidth;
+    ctx.lineJoin = 'round';
+    this.path(pts);
+    ctx.stroke();
+    ctx.globalAlpha = 1;
+  }
+
+  line(x1: number, y1: number, x2: number, y2: number, width: number, color: string, alpha = 1): void {
+    if (alpha <= 0) return;
+    const ctx = this.ctx;
+    ctx.globalAlpha = alpha;
+    ctx.strokeStyle = color;
+    ctx.lineWidth = width;
+    ctx.lineCap = 'round';
+    ctx.beginPath();
+    ctx.moveTo(x1, y1);
+    ctx.lineTo(x2, y2);
+    ctx.stroke();
+    ctx.globalAlpha = 1;
+  }
+
+  fillCircle(cx: number, cy: number, radius: number, color: string, alpha = 1): void {
+    if (alpha <= 0) return;
+    const ctx = this.ctx;
+    ctx.globalAlpha = alpha;
+    ctx.fillStyle = color;
+    ctx.beginPath();
+    ctx.arc(cx, cy, radius, 0, Math.PI * 2);
+    ctx.fill();
+    ctx.globalAlpha = 1;
+  }
+
+  text(s: string, cx: number, cy: number, size: number, color: string, bold = false, alpha = 1): void {
+    if (alpha <= 0) return;
+    const ctx = this.ctx;
+    ctx.globalAlpha = alpha;
+    ctx.fillStyle = color;
+    ctx.font = `${bold ? '700' : '500'} ${size}px ${this.fontFamily}`;
+    ctx.textAlign = 'center';
+    ctx.textBaseline = 'middle';
+    ctx.fillText(s, cx, cy + size * 0.04);
+    ctx.globalAlpha = 1;
+  }
+}