Add module.cpp to expose C++ functions to Python

src/pymatlib/core/cpp/module.cpp

+#include <pybind11/pybind11.h>
+#include <pybind11/numpy.h>
+#include "include/binary_search_interpolation.h"
+#include "include/double_lookup_interpolation.h"
+
+namespace py = pybind11;
+
+PYBIND11_MODULE(fast_interpolation, m) {
+    m.doc() = "Fast interpolation methods implementation";
+
+    m.def("interpolate_binary_search",
+          &interpolate_binary_search,
+          "Find temperature using binary search and linear interpolation",
+          py::arg("temperature_array"),
+          py::arg("h_in"),
+          py::arg("energy_density_array"));
+
+    m.def("interpolate_double_lookup",
+          &interpolate_double_lookup,
+          "Fast interpolation using double lookup method and linear interpolation",
+          py::arg("E_target"),
+          py::arg("T_eq"),
+          py::arg("E_neq"),
+          py::arg("E_eq"),
+          py::arg("idx_map"));
+}