增加笔画生产尺寸与数量报告

按最终矢量页面汇总每个相机单元的笔画包络，并标出低于 0.2 mm 的数量。
已核对 SVG、清单哈希和 Blender 导出，175 项相关测试通过。

README.md

@@ -246,8 +246,14 @@ The stroke output is independent of the color artwork pixels. The revision's
 mode; `--output-dir` selects a fresh destination. `--views` uses the existing
 `texture-views` job's triangle ownership, seam margin and
 per-view page sizes. The command writes PNG/SVG/PDF, resolved settings and a hash manifest.
-The projected-cell ratios do not guarantee a 0.2 mm physical stroke width;
-measure the production SVG before manufacturing.
+It also writes `stroke_texture_production_report.json`: per-view stroke and
+vector-fragment counts, minimum/median/maximum printed width and length in mm,
+the number of strokes below the 0.2 mm width target, and an estimated black
+area ratio. One visible camera cell counts as one stroke even when UV triangles
+split its SVG outline. Width and length are the short and long sides of the
+minimum-area rectangle around the emitted fragments on the print page. This
+envelope does not certify the narrowest local feature or guarantee 0.2 mm
+manufacturing width; inspect the production SVG before manufacturing.
 
 ## Inspect printability (advisory)