First draft of backend independent plugins

backend/plugin/passive_plugin.py

@@ -0,0 +1,15 @@
+class PassivePlugin:
+    def __init__(self, logger) -> None:
+        self.logger
+        pass
+
+    def call_method(self, method_name, args):
+        self.logger.debug(f"Tried to call method {method_name}, but plugin is in passive mode")
+        pass
+
+    def execute_method(self, method_name, method_args):
+        self.logger.debug(f"Tried to execute method {method_name}, but plugin is in passive mode")
+        pass
+
+    async def start(self):
+        pass# Empty stub