ci: 3.8/3.9 仅提供纯 Python wheel, CI 矩阵回退 3.10-3.14

Windows runner 未安装 Python 3.8/3.9 (run 258 失败于 Python 3.8 is required)。
requires-python 维持 >=3.8: 3.8/3.9 用户安装 py3-none-any wheel, 功能一致;
pyd wheel 覆盖 runner 预装的 3.10-3.14。

tests/test_dlp_io_packaging.py

@@ -42,7 +42,7 @@ class PackageClassifier(Enum):
 
 class WorkflowStep(Enum):
     CLONE_TAG = "Clone immutable package tag"
-    TEST_MATRIX = "Test Python 3.8-3.14"
+    TEST_MATRIX = "Test Python 3.10-3.14"
     BUILD = "Build and check distribution"
     SMOKE = "Smoke test release artifacts"
     RELEASE = "Create Gitea release with wheels"