Reorganize emu folder, update S-SMP system infra

test/spc700_test.cc

@@ -0,0 +1,26 @@
+#include "app/emu/audio/spc700.h"
+
+#include <gmock/gmock.h>
+#include <gtest/gtest.h>
+
+namespace yaze {
+namespace app {
+namespace emu {
+
+class MockAudioRAM : public AudioRam {
+ public:
+  MOCK_METHOD(uint8_t, read, (uint16_t address), (const, override));
+  MOCK_METHOD(void, write, (uint16_t address, uint8_t value), (override));
+};
+
+class SPC700Test : public ::testing::Test {
+ protected:
+  SPC700Test() = default;
+
+  MockAudioRAM audioRAM;
+  SPC700 spc700{audioRAM};
+};
+
+}  // namespace emu
+}  // namespace app
+}  // namespace yaze