release: v1.7.0 - region-agnostic skeleton, selectable true-black, English code

Highlights:

- minimum mode: add min_true_black switch (default True = unchanged v1.6.1 behaviour).

  True  : true-black gate + CC denoise (best for black line work).

  False : no gate, keeps colored regions, distance-transform thinning

          (best for colorful posters).

- skeleton mode: replace hue-specific green-block smoothing with

  saturation-based _color_zones; no hue or side-of-image assumptions.

- Move all comments, docstrings and messages to English.

- Remove built-in default paths; examples/demo.py now requires args.

- README: document both minimum variants, resolution guidance, parameters.

- tests: 18 cases covering I/O, both modes, both minimum variants.

pyproject.toml

@@ -4,8 +4,8 @@ build-backend = "setuptools.build_meta"
 
 [project]
 name = "lineartization"
-version = "1.6.1"
-description = "彩色插图/手抄报 一键转换为黑白线稿 (汉字清晰、线条连贯、粗细统一)"
+version = "1.7.0"
+description = "Convert color illustrations and posters into clean black-and-white line art."
 readme = "README.md"
 requires-python = ">=3.8"
 license = { text = "MIT" }
@@ -14,7 +14,7 @@ authors = [
 ]
 keywords = [
     "lineart", "line-art", "sketch", "skeleton", "thinning",
-    "image-processing", "opencv", "手抄报", "线稿", "提取线稿",
+    "image-processing", "opencv", "poster", "line-extraction",
 ]
 classifiers = [
     "Development Status :: 5 - Production/Stable",