feat(DemoStandardPath): migrate the demo to the MachiningProject schema and add the circle-test path

Main.hincproj moves off the legacy <MillingCourse> root onto <MachiningProject>,
so its six 範例 script entries are now EnablingWrapper-based and it carries an
explicit MillingTool (helix 50 deg, 28 mm exposed). The materials follow the same
rename: HeatTransferCoefficient_WdmK -> HeatConductivity_WdmK, and Al6061T6.mp
becomes RakeFaceCuttingPara3d with an AnchorRakeAngle_deg field.

Because of that root-element change the ApiVersion string reads lower (3.1.200.0)
than the legacy copy it replaces (3.1.236.0) -- the two counters are not
comparable across the rename.

Adds NC/circle-test.ptp with its posted Output/circle.ptp.nc, plus test.hincproj;
ignores the *.step.csv exports and filtered-msg.txt.

Al6061T6.mp

@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
-<RakeFaceCuttingPara>
+<RakeFaceCuttingPara3d>
   <Name>Al6061T6</Name>
   <Note></Note>
   <Kse>141.27</Kse>
@@ -8,4 +8,5 @@
   <Kpe>-1.96</Kpe>
   <Kpc>5.54</Kpc>
   <Kpn>-21.51</Kpn>
-</RakeFaceCuttingPara>
+  <AnchorRakeAngle_deg>NaN</AnchorRakeAngle_deg>
+</RakeFaceCuttingPara3d>