v0.4.1: 圆环图标签优化 / Donut chart label improvement

Patch release fixing label overlap in analytics donut charts.

🐛 Bug fixes

分析看板币种总览圆环图标签重叠：当某币种下资产或负债构成包含多个小占比项目时，原有标签和引导线会彼此重叠。现在布局引擎会先尝试纵向错开标签，空间仍不足时自动隐藏重叠的标签——完整数据不出现在图表标签上，但始终可通过图例和 Tooltip 查看。

Analytics currency donut chart label overlap: when a currency's asset or liability breakdown includes many small-share items, the previous layout let labels and guide lines collide. The improved layout now shifts labels vertically first, then hides remaining overlaps — data not shown on chart labels is always accessible via the legend and tooltip.