接续上一轮：推进浏览器验证与M428配置收拢

结论：已完成浏览器侧真实加载验证，M428/M429/M430 的配置入口进一步从 LinuxCNC INI/HALFILE/REMAP 来源生成，native 与 source-link 验证通过。

core/tools/cnc_sim_dump.cpp

@@ -107,6 +107,8 @@ int main(int argc, char **argv) {
     CncSimHandle *sim = cnc_sim_create();
     bool first = true;
     cnc_sim_set_event_callback(sim, print_event, &first);
+    const char smoke_config[] = "{\"backend\":\"smoke\"}";
+    cnc_sim_load_config_json(sim, smoke_config, sizeof(smoke_config) - 1);
 
     std::cout << "[\n";
     const int rc = cnc_sim_parse_program(sim, program.c_str(), program.size());

core/tools/linuxcnc_rs274_dump.cpp

@@ -143,7 +143,10 @@ bool execute_line(InterpBase *interp,
     if (parse_simulator_gcode_control_line(line, &control_actions)) {
         bool simulator_only_line = true;
         for (const auto &action : control_actions) {
-            emit_simulator_gcode_control_action(sink, action, line_number);
+            const bool handled = emit_simulator_gcode_control_action(sink, action, line_number);
+            if (!handled) {
+                simulator_only_line = false;
+            }
             if (action.kind == SimulatorGcodeControlKind::RtcpState &&
                 !action.rtcp_enabled) {
                 simulator_only_line = false;