[loop-cycle-62] fix: MEMORY.md corruption and hot memory staleness (#252) (#256)

src/timmy/thinking.py

@@ -743,7 +743,7 @@ class ThinkingEngine:
         Never modifies soul.md. Never crashes the heartbeat.
         """
         try:
-            from timmy.memory_system import memory_system
+            from timmy.memory_system import store_last_reflection
 
             ts = datetime.fromisoformat(thought.created_at)
             local_ts = ts.astimezone()
@@ -754,7 +754,7 @@ class ThinkingEngine:
                 f"**Seed:** {thought.seed_type}\n"
                 f"**Thought:** {thought.content[:200]}"
             )
-            memory_system.hot.update_section("Last Reflection", reflection)
+            store_last_reflection(reflection)
         except Exception as exc:
             logger.debug("Failed to update memory after thought: %s", exc)