Create snes_asm namespace for MosaicEditor code

src/app/asm/script.h

@@ -0,0 +1,28 @@
+#ifndef YAZE_APP_ASM_SCRIPT_H
+#define YAZE_APP_ASM_SCRIPT_H
+
+#include <asar.h>
+
+#include <array>
+#include <fstream>
+#include <sstream>
+
+#include "absl/status/statusor.h"
+#include "absl/strings/string_view.h"
+#include "app/core/constants.h"
+
+namespace yaze {
+namespace app {
+namespace snes_asm {
+
+using MosaicArray = std::array<int, core::kNumOverworldMaps>;
+constexpr char kDefaultMosaicHook[] = "$02AADB";
+
+absl::StatusOr<absl::string_view> GenerateMosaicChangeAssembly(
+    MosaicArray mosaic_tiles);
+
+}  // namespace snes_asm
+}  // namespace app
+}  // namespace yaze
+
+#endif