fix: correct typing, simplify logs

ref: N25B-299

src/control_backend/agents/bdi/bdi_program_manager.py

@@ -52,7 +52,7 @@ class BDIProgramManager(BaseAgent):
             try:
                 program = Program.model_validate_json(body)
             except ValidationError as e:
-                self.logger.error("Received an invalid program.", exc_info=e)
+                self.logger.exception("Received an invalid program.")
                 continue
 
             await self._send_to_bdi(program)

src/control_backend/agents/llm/llm_instructions.py

@@ -17,7 +17,7 @@ class LLMInstructions:
             "Try to learn the user's name during conversation.",
         ]
 
-    def __init__(self, norms: list[str] = None, goals: list[str] = None):
+    def __init__(self, norms: list[str] | None = None, goals: list[str] | None = None):
         self.norms = norms or self.default_norms()
         self.goals = goals or self.default_goals()