v1.2.3

修复

• 柱状图最左柱压住纵轴刻度 —— 柱子不再越出绘图区，刻度与悬停位置不变；折线视图不受影响。
• 热力图星期标签与格子错行 —— 标签重新对齐到各自的格子行。
• 热力图悬停提示不显示 —— 提示框改按屏幕定位，不再被面板裁掉。
• 浅色主题下图表与日历看不清 —— 数据色改为跟随主题，浅色对比度达标，深色外观不变。

优化

• 面板改为浮动圆角卡片 —— 四角圆角、四周留边，窄窗口不再退化成直角。
• 标题栏独立成圆角卡片 —— 下边框换成柔和阴影，滚动时停在拖拽条下方。

Fixes

• The leftmost bar covers the y-axis labels — bars stay inside the plot; ticks and hover targets are unchanged, and the line view is untouched.
• Heatmap weekday labels drift off their rows — each label lines up with its grid row again.
• The heatmap tooltip never shows up — it is positioned against the screen again instead of being clipped by the panel.
• Charts and the calendar are hard to read on a light theme — data colours follow the theme; light passes contrast and the dark look is unchanged.

Improvements

• The panel is a floating rounded card — rounded on all four corners with a margin, so a narrow window no longer squares it off.
• The toolbar is a rounded card of its own — the hard bottom border becomes a soft shadow, and it parks under the drag strip while scrolling.