feat: add candidate FreeCAD naming SDK and attachment oracles

Build and verify the candidate-only FreeCAD naming bridge and OCCT worker path, including three-stage StringHasher restoration. Add Datum, ShapeBinder, attachment-mode, and PartDesign structure oracles plus offline SDK build plans and CI boundary checks.

native/freecad-naming-probe/shims/Base/Stream.h

@@ -0,0 +1,43 @@
+#pragma once
+
+#include <istream>
+#include <ostream>
+#include <string>
+
+namespace Base {
+
+class TextOutputStream
+{
+public:
+    explicit TextOutputStream(std::ostream& stream)
+        : output(stream)
+    {}
+
+    TextOutputStream& operator<<(const char* value)
+    {
+        output << value;
+        return *this;
+    }
+
+private:
+    std::ostream& output;
+};
+
+class TextInputStream
+{
+public:
+    explicit TextInputStream(std::istream& stream)
+        : input(stream)
+    {}
+
+    TextInputStream& operator>>(std::string& value)
+    {
+        input >> value;
+        return *this;
+    }
+
+private:
+    std::istream& input;
+};
+
+}  // namespace Base