fix: handle missing files

src/core/palette/palette_manager.hpp

@@ -2,6 +2,7 @@
 #define CLRSYNC_CORE_PALETTE_PALETTE_MANAGER_HPP
 
 #include "core/utils.hpp"
+#include <iostream>
 #include <string>
 #include <unordered_map>
 
@@ -19,6 +20,11 @@ template <typename FileType> class palette_manager
     void load_palettes_from_directory(const std::string &directory_path)
     {
         auto directory_path_expanded = expand_user(directory_path);
+        if (!std::filesystem::exists(directory_path_expanded))
+        {
+            std::cerr << "Palettes directory does not exist\n" ;
+            return;
+        }
         for (const auto &entry : std::filesystem::directory_iterator(directory_path_expanded))
         {
             if (entry.is_regular_file())