Update fillet+chamfer with new API options

rust/kcl-lib/std/cutStrategy.kcl

@@ -0,0 +1,9 @@
+@no_std
+@settings(defaultLengthUnit = mm, kclVersion = 1.0)
+
+/// Try the fast but simple Basic strategy, and if that fails, try the slow and complex CSG strategy.
+export automatic = "automatic"
+/// The basic strategy is fastest, but it can't handle complicated cases (like chamfering two edges that touch).
+export basic = "basic"
+/// The CSG strategy is slowest, but it can handle complex cases (like chamfering two edges that touch).
+export csg = "csg"

rust/kcl-lib/std/prelude.kcl

@@ -16,6 +16,7 @@ export import * from "std::sketch"
 export import * from "std::solid"
 export import * from "std::transform"
 export import "std::turns"
+export import "std::cutStrategy"
 
 export XY = {
   origin = { x = 0, y = 0, z = 0 },

rust/kcl-lib/std/solid.kcl

@@ -71,6 +71,8 @@ export fn fillet(
   tolerance?: number(Length),
   /// Create a new tag which refers to this fillet
   tag?: tag,
+  /// Which strategy should be used to perform this chamfer?
+  strategy?: string,
 ): Solid {}
 
 /// Cut a straight transitional edge along a tagged path.
@@ -146,6 +148,8 @@ export fn chamfer(
   tags: [Edge; 1+],
   /// Create a new tag which refers to this chamfer
   tag?: tag,
+  /// Which strategy should be used to perform this chamfer?
+  strategy?: string,
 ): Solid {}
 
 /// Remove volume from a 3-dimensional shape such that a wall of the