CAM: Convert tapping operation to experimental feature, Add tap pitch support, improve tapping logic, and update toolbit schema and legacy linuxcnc post

CAM/App/PathSegmentWalker.cpp
- Add G74 to drill/tap/bore G-code recognition for tapping cycles

CAM/InitGui.py
- Move CAM_Tapping command behind experimental feature flag
- Only group drilling/tapping commands if both are enabled

CAM/Path/Base/Generator/tapping.py
- Add pitch and spindle_speed parameters to tapping.generate
- Output S (spindle speed) and F (pitch) in generated G-code

CAM/Path/Op/Tapping.py
- Require Pitch property for tap tools and SpindleSpeed for tool controllers
- Pass pitch and spindle speed to tapping.generate
- Use SpindleDirection to determine right/left hand tap

CAM/Path/Post/scripts/linuxcnc_post.py
- Handle G84/G74 tapping cycles: convert pitch and spindle speed to feed rate
- Remove F and S from output and recalculate F as needed

CAM/Path/Tool/shape/models/tap.py
- Add Pitch property to ToolBitShapeTap schema
- CAM/Path/Tool/toolbit/models/tap.py
- Show pitch and rotation in tap tool summary
- Use is_imperial_pitch to format pitch as TPI or mm

CAM/Path/Tool/toolbit/util.py
- Add is_imperial_pitch utility to classify pitch as imperial or metric

CAM/Tools/Bit/375-16_Tap.fctb
- Remove unused parameters (Coating, Rotation, TPI, Type)
- Keep only relevant tap parameters for new schema

src/Mod/CAM/Path/Tool/shape/models/tap.py

@@ -56,6 +56,10 @@ class ToolBitShapeTap(ToolBitShape):
                 FreeCAD.Qt.translate("ToolBitShape", "Tip angle"),
                 "App::PropertyAngle",
             ),
+            "Pitch": (
+                FreeCAD.Qt.translate("ToolBitShape", "Thread pitch"),
+                "App::PropertyLength",
+            ),
         }
 
     @property

src/Mod/CAM/Path/Tool/toolbit/models/tap.py

@@ -24,6 +24,7 @@ import Path
 from ...shape import ToolBitShapeTap
 from ..mixins import RotaryToolBitMixin, CuttingToolMixin
 from .base import ToolBit
+from ..util import is_imperial_pitch
 
 
 class ToolBitTap(ToolBit, CuttingToolMixin, RotaryToolBitMixin):
@@ -39,7 +40,34 @@ class ToolBitTap(ToolBit, CuttingToolMixin, RotaryToolBitMixin):
         diameter = self.get_property_str("Diameter", "?", precision=3)
         flutes = self.get_property("Flutes")
         cutting_edge_length = self.get_property_str("CuttingEdgeLength", "?", precision=3)
+        pitch_raw = self.get_property("Pitch")
+
+        spindle_direction = self.get_property_str("SpindleDirection", "Forward")
+        if spindle_direction == "Forward":
+            rotation = "Right Hand"
+        elif spindle_direction == "Reverse":
+            rotation = "Left Hand"
+        else:
+            rotation = spindle_direction
+
+        if isinstance(pitch_raw, FreeCAD.Units.Quantity):
+            pitch_mm = pitch_raw.getValueAs("mm")
+        else:
+            pitch_mm = FreeCAD.Units.Quantity(str(pitch_raw)).getValueAs("mm")
+
+        if pitch_raw:
+            try:
+                if is_imperial_pitch(pitch_raw):
+                    tpi = round(25.4 / pitch_mm, 2)
+                    pitch = f"{int(tpi) if tpi == int(tpi) else tpi} TPI"
+                else:
+                    pitch = f"{pitch_mm} mm"
+            except Exception:
+                pitch = str(pitch_raw)
+        else:
+            pitch = "?"
 
         return FreeCAD.Qt.translate(
-            "CAM", f"{diameter} tap, {flutes}-flute, {cutting_edge_length} cutting edge"
+            "CAM",
+            f"{diameter} {pitch} {rotation} tap, {flutes}-flute, {cutting_edge_length} cutting edge",
         )

src/Mod/CAM/Path/Tool/toolbit/util.py

@@ -47,3 +47,33 @@ def format_value(value: FreeCAD.Units.Quantity | int | float | None, precision:
             return value.getUserPreferred()[0]
         return value.UserString
     return str(value)
+
+
+def is_imperial_pitch(pitch_mm, tol=1e-6):
+    """
+    Classify a pitch in mm as imperial vs metric.
+    Rule:
+        - If pitch_mm is ~2 decimal places clean -> metric,
+        unless it corresponds to an exact whole-number TPI.
+        - Otherwise, treat as imperial.
+    """
+    import math
+
+    try:
+        mm = float(pitch_mm)
+    except Exception:
+        return False
+    if mm <= 0:
+        return False
+
+    # Check if it's "two-decimal clean"
+    two_dec_clean = abs(mm - round(mm, 2)) <= tol
+
+    # Compute TPI
+    tpi = 25.4 / mm
+    whole_tpi = round(tpi)
+    is_whole_tpi = math.isclose(tpi, whole_tpi, abs_tol=1e-6)
+
+    if two_dec_clean and not is_whole_tpi:
+        return False  # metric
+    return True  # imperial