10C Inc 3 + 4: I/O and text — the app's whole OCP surface is bound

138/138 symbols across 53 modules. New: IFSelect, Interface, XSControl,
IGESData, STEPControl, IGESControl, RWStl, Graphic3d, NCollection, StdPrs.

**The full app suite passes against this wheel: 1797 passed, 1 skipped — the
same result as the stock wheel**, run from the parity venv.

Getting there needed six methods that no static analysis could have found:
`inventory --check` only sees symbols reached through an import, so a method
called on an instance is invisible to it. The suite found them in one pass, and
one of them (gp_Vec.Reverse, which every outward-normal probe calls) accounted
for 311 of the 255 failing tests on its own. The others: gp_Trsf.SetMirror over
a plane and a point, Geom_Surface.D0, BRep_Builder.MakeFace from a
triangulation, MakePipeShell.SetMode with a fixed binormal, and MakeFace from a
surface plus tolerance.

Open question **S5 is settled: no**. The wheel does not need OCCT's share/
resources. test_inc3_io.py asserts no CSF_* variable is set and then round-trips
STEP and IGES, reading the declared units back off both — which is exactly the
resource-less container the question was about.

The XSTEP readers keep the GIL, amending the blanket "file readers and writers"
line in design.md's GIL policy. STEP and IGES traffic in process-global
Interface_Static state, the IGES reader is documented as not thread-safe, and
the app already serialises imports behind a lock — so holding it costs nothing
and removes a class of question. RWStl, which touches no global state, releases.

XSControl_Reader and IGESData are registered although the app imports neither:
they are the reader base both concrete readers inherit their transfer surface
from, and the model-to-global-section chain the IGES unit probe walks.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01DfriM8XUkn7uYf5Dwe2xo6

src/modules/mod_StdPrs.cpp

@@ -0,0 +1,57 @@
+/*
+    OCP.StdPrs — glyph outlines as BRep.
+
+    Text emboss loads a bundled font and asks the builder for the text as a
+    compound of face outlines, holes already subtracted, which it then extrudes
+    into or out of the model.
+
+    These live in TKService, and both classes are real in 7.9.3 rather than the
+    deprecated typedefs of Font_BRepFont/Font_BRepTextBuilder that OCCT 8.0
+    turns them into — so the 8.0 port is a rename here and nothing else.  The
+    builder image already asserts TKService links without libGL or libX11, so
+    binding them costs the runtime image nothing.
+
+    Rendering a glyph is FreeType work with no Python in it, so it releases the
+    GIL.
+*/
+
+#include "../common/occt_module.h"
+#include "../common/occt_policies.h"
+#include "../common/occt_transient.h"
+
+#include <NCollection_String.hxx>
+#include <StdPrs_BRepFont.hxx>
+#include <StdPrs_BRepTextBuilder.hxx>
+#include <TopoDS_Shape.hxx>
+#include <gp_Ax3.hxx>
+
+void register_StdPrs(nb::module_ &root) {
+    nb::module_ m = ocp_submodule(root, "StdPrs");
+
+    nb::class_<StdPrs_BRepFont, Standard_Transient>(m, "StdPrs_BRepFont")
+        .def(ocp_new<StdPrs_BRepFont>())
+        .def(
+            "Init",
+            [](StdPrs_BRepFont &self, const NCollection_String &path,
+               const Standard_Real size, const Standard_Integer faceId) {
+                return self.Init(path, size, faceId);
+            },
+            "theFontPath"_a, "theSize"_a, "theFaceId"_a, OCP_NOGIL)
+        .def("Release", &StdPrs_BRepFont::Release)
+        .def("Ascender", &StdPrs_BRepFont::Ascender)
+        .def("Descender", &StdPrs_BRepFont::Descender);
+
+    nb::class_<StdPrs_BRepTextBuilder>(m, "StdPrs_BRepTextBuilder")
+        .def(nb::init<>())
+        .def(
+            "Perform",
+            [](StdPrs_BRepTextBuilder &self, StdPrs_BRepFont &font,
+               const NCollection_String &text, const gp_Ax3 &penLoc,
+               const Graphic3d_HorizontalTextAlignment hAlign,
+               const Graphic3d_VerticalTextAlignment vAlign) {
+                return self.Perform(font, text, penLoc, hAlign, vAlign);
+            },
+            "theFont"_a, "theString"_a, "thePenLoc"_a = gp_Ax3(),
+            "theHAlign"_a = Graphic3d_HTA_LEFT,
+            "theVAlign"_a = Graphic3d_VTA_BOTTOM, OCP_RETURN_COPY, OCP_NOGIL);
+}