按建议，继续完成后续工作

结论：新增并接入 emcStatus 机器单位边界探针，native 验证链通过。

wasm-port/runtime/core/linuxcnc_wrap/linuxcnc_emc_status_probe.cpp

@@ -1,4 +1,39 @@
 #include "nml_intf/emc.hh"
 
+#include <iostream>
+
 static EMC_STAT standalone_emc_status;
 EMC_STAT *emcStatus = &standalone_emc_status;
+
+int main()
+{
+    const bool default_units_visible = emcStatus->motion.traj.linearUnits == 1.0;
+    const bool default_machine_units_mm =
+        emcStatus->motion.traj.linearUnits > 0.5;
+
+    emcStatus->motion.traj.linearUnits = 1.0 / 25.4;
+    const bool inch_machine_units_visible =
+        emcStatus->motion.traj.linearUnits <= 0.5;
+
+    emcStatus->motion.traj.linearUnits = 1.0;
+    const bool mm_machine_units_visible =
+        emcStatus->motion.traj.linearUnits > 0.5;
+
+    std::cout << "emc_status_default_linear_units="
+              << emcStatus->motion.traj.linearUnits << "\n";
+    std::cout << "emc_status_default_units_visible="
+              << default_units_visible << "\n";
+    std::cout << "emc_status_default_machine_units_mm="
+              << default_machine_units_mm << "\n";
+    std::cout << "emc_status_inch_machine_units_visible="
+              << inch_machine_units_visible << "\n";
+    std::cout << "emc_status_mm_machine_units_visible="
+              << mm_machine_units_visible << "\n";
+
+    if (!default_units_visible || !default_machine_units_mm ||
+        !inch_machine_units_visible || !mm_machine_units_visible) {
+        return 1;
+    }
+
+    return 0;
+}