Add EditorContext, refactor utils, add system managers

src/app/editor/system/history_manager.h

@@ -0,0 +1,32 @@
+#ifndef YAZE_APP_EDITOR_SYSTEM_HISTORY_MANAGER_H
+#define YAZE_APP_EDITOR_SYSTEM_HISTORY_MANAGER_H
+
+#include <cstddef>
+#include <stack>
+#include <vector>
+
+namespace yaze {
+namespace app {
+namespace editor {
+
+// System history manager, undo and redo.
+class HistoryManager {
+ public:
+  HistoryManager() = default;
+  ~HistoryManager() = default;
+
+  void Add(const char* data);
+  void Undo();
+  void Redo();
+
+ private:
+  std::vector<const char*> history_;
+  std::stack<const char*> undo_;
+  std::stack<const char*> redo_;
+};
+
+}  // namespace editor
+}  // namespace app
+}  // namespace yaze
+
+#endif  // YAZE_APP_EDITOR_SYSTEM_HISTORY_MANAGER_H