Refactor ROM handling and update Overworld methods

Updated MessageEditor, RoomEntrance, and Overworld classes to use WriteByte instead of Write for byte values. Refactored ROM class by removing Write and toint16 methods, moving constants, and updating operator[]. Modified Overworld methods to return absl::Status and handle errors. Updated Inventory and OverworldMap methods to use ReadWord instead of toint16.

src/app/zelda3/overworld/overworld.h

@@ -114,13 +114,14 @@ class Overworld : public SharedRom {
   absl::Status Load(Rom &rom);
   absl::Status LoadOverworldMaps();
   void LoadTileTypes();
-  void LoadEntrances();
+  absl::Status LoadEntrances();
+  absl::Status LoadHoles();
 
   absl::Status LoadExits();
   absl::Status LoadItems();
   absl::Status LoadSprites();
-  absl::Status LoadSpritesFromMap(int spriteStart, int spriteCount,
-                                  int spriteIndex);
+  absl::Status LoadSpritesFromMap(int sprite_start, int sprite_count,
+                                  int sprite_index);
 
   absl::Status Save(Rom &rom);
   absl::Status SaveOverworldMaps();
@@ -145,7 +146,9 @@ class Overworld : public SharedRom {
     all_entrances_.clear();
     all_exits_.clear();
     all_items_.clear();
-    all_sprites_.clear();
+		for (auto& sprites : all_sprites_) {
+			sprites.clear();
+		}
     is_loaded_ = false;
   }