refactor: use JSON for settings

lnbits/settings.py

@@ -1,4 +1,5 @@
 import importlib
+import inspect
 import json
 import subprocess
 from os import path
@@ -197,6 +198,12 @@ class EditableSetings(
     def validate_editable_settings(cls, val):
         return super().validate(cls, val)
 
+    @classmethod
+    def from_dict(cls, d: dict):
+        return cls(
+            **{k: v for k, v in d.items() if k in inspect.signature(cls).parameters}
+        )
+
 
 class ReadOnlySettings(LNbitsSetings):
     lnbits_admin_ui: bool = Field(default=False)