v0.2.0

What's New

New Plot Types

• Scatter plots with color and size mapping: draw_scatter, draw_scatter_color, draw_scatter_size, draw_scatter_color_size
• Heatmaps: draw_heatmap (matrix and vector variants)
• Contour plots: draw_contour, draw_contour_filled, contour_levels
• Box plots: draw_boxplot for single and grouped data
• Grouped/stacked bar charts: draw_grouped_bars, draw_stacked_bars
• 3D surfaces: draw_surface, draw_surface_mesh

New Features

• Dual Y-axis support: y2label, y2range, y2tics_show, draw_curve_y2, draw_points_y2
• Log scale convenience methods: xlog, ylog, xylog, zlog, xyzlog, xlog_off, ylog_off
• Date/time axis: xtime_format, xtime_display, ytime_format, ytime_display
• Annotations: annotate, annotate_graph, arrow, arrow_graph, hline, vline
• Draw options: axes (for secondary axis), palette_use, variable_point_size

Bug Fixes

• Fixed typo in BasePlot#clear (@customcmdss → @customcmds)
• Fixed missing title output in Plot3D#repr
• Fixed typo in Plot#draw_steps calling non-existent method
• Fixed linestyle overriding explicit linecolor settings

Other

• Expanded test coverage (23 → 125 examples)
• Updated shard description- Added example: stock-analysis.cr, scientific-scatter.cr