feat(cadfs): 补齐核心建模能力并建立代表性回归

- 新增 loft、双向切除、through-all/up-to-next 等 CADFS lowering 与 engine 支持
- 支持多种 reference plane、B-spline profile 和 circular pattern replay
- 保留 transform 历史，并烘焙安全的单源平移/旋转变换
- 改进 selector 绑定、拓扑快照和 pattern 变换处理
- 建立 17 个代表样本的转换、重建与比较回归工具链
- 补充 schema、author guidance、运行时和几何回归测试

cadfs_to_cdsl/reports.py

@@ -184,11 +184,12 @@ def generate_markdown_report(
     )
 
     unsupported_ops = {
-        "shell", "loft", "sweep", "draft", "thicken", "split", "booleanBodies", "circularPattern",
+        "shell", "sweep", "draft", "thicken", "split", "booleanBodies", "circularPattern",
         "moveFace", "replaceFace", "deleteFace", "import", "derive",
     }
     exact_mappings = {
         "extrude": "extrude_add_blind / extrude_add_two_sided / extrude_cut_blind",
+        "loft": "loft_add (simple closed sketch profiles only)",
         "revolve": "revolve_add / revolve_cut",
         "fillet": "fillet",
         "chamfer": "chamfer",