Machining model and materials (#14460)

* Machining model and materials

Adds a few machinability material model
and a couple materials.  There's a button in the job dialog
to assign a material.

The sanity report is updated to display the surface speed for assigned materials

* improving the machinability model

* Introduce MaterialConstant for the machinability model

This constant is required to calculate the actual specific cutting force
from the normalized value. It determines how the actaual value varies
when the actual chip thickness gets further away from the normalization
point.

* Rename some machinability properties

- SpecificCuttingForce becomes UnitCuttingForce to clearer differentiate
between normalized and actual specific cutting force. The term unit
cutting force is used less often in literature, but
NormalizedSpecificCuttingForce as property name is too long for my taste.
- MaterialConstant becomes ChipThicknessExponent, as "material constant"
is just too generic for our context. In literature, this constant is most
often just used as the symbol m_c.

---------

Co-authored-by: Jonas Bähr <jonas.baehr@web.de>

src/Mod/Material/App/ModelUuids.cpp

@@ -34,6 +34,9 @@ const QString ModelUUIDs::ModelUUID_Legacy_Father =
 const QString ModelUUIDs::ModelUUID_Legacy_MaterialStandard =
     QString::fromStdString("1e2c0088-904a-4537-925f-64064c07d700");
 
+const QString ModelUUIDs::ModelUUID_Machining_Machinability =
+    QString::fromStdString("9d81fcb2-bf81-48e3-bb57-d45ecf380096");
+
 const QString ModelUUIDs::ModelUUID_Mechanical_ArrudaBoyce =
     QString::fromStdString("e10d00de-c7de-4e59-bcdd-058c2ea19ec6");
 const QString ModelUUIDs::ModelUUID_Mechanical_Density =