fix(simple_metrics): skip invalid interval_minutes and restart a malformed healthy_streak (SIENTIAPDE-2191)

- interval_minutes is untyped Mongo config: a string or null now warns and
  skips the adaptive state instead of failing every run (TypeError).
- A hand-edited healthy_streak (null, text, inf) restarts the count and keeps
  escalated, instead of raising on every run.
- README: step 4 runs on every schedule, so a MongoDB failure fails the run.

laborious/activities/model_metrics.py

@@ -85,7 +85,10 @@ def next_adaptive_state(state: dict[str, Any], breached: bool, runs: int) -> dic
         return {'escalated': True, 'healthy_streak': 0}
     if not state.get('escalated'):
         return {'escalated': False, 'healthy_streak': 0}
-    streak = int(state.get('healthy_streak', 0)) + 1
+    try:
+        streak = int(state.get('healthy_streak', 0)) + 1
+    except (TypeError, ValueError, OverflowError):
+        streak = 1  # hand-edited streak (null, text, inf): restart the count, stay escalated
     if streak >= runs:
         return {'escalated': False, 'healthy_streak': 0}
     return {'escalated': True, 'healthy_streak': streak}

laborious/activities/mongo.py

@@ -192,11 +192,14 @@ class MongoActivities(SientiaMonitoring):
 
         try:
             runs = recovery_runs(input_data['interval_minutes'], str(frequency_alert))
-        except ValueError:
-            # Config error, not a failure: the orchestrator ignores this value too (keeps
-            # `frequency`) and already sends SIMPLE_METRICS_FREQUENCY_ALERT_BELOW_FLOOR for it.
+        except (TypeError, ValueError):
+            # Config error, not a failure: the orchestrator ignores an invalid `frequency_alert`
+            # too (keeps `frequency`) and already sends SIMPLE_METRICS_FREQUENCY_ALERT_BELOW_FLOOR
+            # for it. `interval_minutes` is untyped Mongo config as well (e.g. "60" or null).
             self.warning(
-                f'Invalid frequency_alert={frequency_alert!r}: adaptive state skipped', metadata
+                f'Invalid frequency_alert={frequency_alert!r} or '
+                f'interval_minutes={input_data["interval_minutes"]!r}: adaptive state skipped',
+                metadata,
             )
             return None