fix(ai): configure OLLAMA_KEEP_ALIVE=5m to automatically release RAM after inactivity

docker-compose.yml

@@ -18,6 +18,7 @@ services:
       - DB_PATH=/app/data/notes.db
       - OLLAMA_BASE_URL=http://ollama:11434
       - OLLAMA_MODEL=qwen2.5:3b
+      - OLLAMA_KEEP_ALIVE=5m
     depends_on:
       - ollama
 
@@ -30,4 +31,4 @@ services:
     volumes:
       - ./data/ollama:/root/.ollama
     environment:
-      - OLLAMA_KEEP_ALIVE=24h
+      - OLLAMA_KEEP_ALIVE=5m