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.

NC/circle-test.ptp

@@ -0,0 +1,21 @@
+%
+N0010 G40 G17 G49 G90
+N0020 G91 G28 Z0.0
+N0030 T01 M06
+N0040 G00 G90 G54
+N0050 X35. Y-11.7
+N0060 G43 Z10. H01
+N0070 S5000 M03
+N0080 M08
+N0090 Z-2.
+N0100 G94 G01 Z-0.01 F500.
+N0110 Y-4.
+N0120 G02 I0.0 J11.
+N0130 G01 Y-10.
+N0140 Z-2.
+N0150 G00 Z10.
+N0160 M09
+N0170 M05
+N0180 G91 G28 Z0.0
+N0190 M30
+%