initial switch to a devcontainer

.devcontainer/compose.yml

@@ -0,0 +1,29 @@
+services:
+  dev:
+    build:
+      context: .
+      dockerfile: Dockerfile
+    command: sleep infinity
+    volumes:
+      - ..:/workspaces/max:cached
+      - home:/home/dev
+    environment:
+      - PYTHONPATH=/workspaces/max
+      - FLASK_APP=max.app
+      - FLASK_ENV=development
+      - PGSQL_HOST=postgresql
+      - PGSQL_PORT=5432
+      - PGSQL_USER=max
+      - PGSQL_PASSWORD=max
+      - PGSQL_NAME=max
+    depends_on:
+      - postgresql
+  postgresql:
+    image: postgres:18.6
+    environment:
+      - POSTGRES_USER=max
+      - POSTGRES_PASSWORD=max
+      - POSTGRES_DB=max
+volumes:
+  home:
+    name: max-devcontainer-home