feat: Store timestamps as strings in the database, which was causing postgres errors.

docker/docker-compose.yaml

@@ -1,4 +1,3 @@
-
 services:
   db:
     image: docker.io/postgres:18
@@ -8,7 +7,9 @@ services:
       - ./data:/var/lib/postgresql
   
   app:
-    image: ghcr.io/m-housh/ductcalc:latest
+    build:
+      dockerfile: docker/Dockerfile
+      context: .
     restart: unless-stopped
     env_file: .env
     depends_on: