Create more oppurtinities for state saving;

for image cache and settings

settings.py

@@ -50,6 +50,7 @@ class Settings:
     def __init__(self, args: ParsedArgs):
         self._settings: SettingsFile = json_load(SETTINGS_PATH, default_settings)
         self._args: ParsedArgs = args
+        self._altered: bool = False
 
     # default logic of reading settings is to check args first, then the settings file
     def __getattr__(self, name: str, /) -> Any:
@@ -65,6 +66,7 @@ class Settings:
             return super().__setattr__(name, value)
         elif name in self._settings:
             self._settings[name] = value  # type: ignore[literal-required]
+            self._altered = True
             return
         raise TypeError(f"{name} is missing a custom setter")
 
@@ -72,4 +74,5 @@ class Settings:
         raise RuntimeError("settings can't be deleted")
 
     def save(self) -> None:
-        json_save(SETTINGS_PATH, self._settings)
+        if self._altered:
+            json_save(SETTINGS_PATH, self._settings)