Squashed commit of the following:

commit cb82580f868b629902ba96c7f09f885b7d9c24dc
Author: Jens Luedicke <jens.luedicke@gmail.com>
Date:   Thu Jul 3 22:42:49 2025 +0200

    Fix for postgres db migration. #5

commit 6a4505e2db1cdb2cec65e630b63535ba08c02fc4
Author: Jens Luedicke <jens.luedicke@gmail.com>
Date:   Thu Jul 3 22:39:58 2025 +0200

    Fix for postgres db migration. #4

commit 7d9a5bb12c591182e67d7d52f90d6b1a45260d9f
Author: Jens Luedicke <jens.luedicke@gmail.com>
Date:   Thu Jul 3 22:38:02 2025 +0200

    Fix for postgres db migration. #3

commit 29dbb8b62d873dfbc4901b21e637a7181d545ec7
Author: Jens Luedicke <jens.luedicke@gmail.com>
Date:   Thu Jul 3 22:35:08 2025 +0200

    Fix for postgres db migration. #2

commit d5afc56290d05f53e06a77366214c605d0989c1d
Author: Jens Luedicke <jens.luedicke@gmail.com>
Date:   Thu Jul 3 22:33:09 2025 +0200

    Fix for postgres db migration.

commit 936008fe1c56b6e699c4a45b503507b6423e15eb
Author: Jens Luedicke <jens.luedicke@gmail.com>
Date:   Thu Jul 3 21:46:32 2025 +0200

    Add changes for gunicorn.

commit 464c71e5102117f35d05e1504165299ffa50c70c
Author: Jens Luedicke <jens.luedicke@gmail.com>
Date:   Thu Jul 3 20:30:29 2025 +0200

    Add changes for Postgres migration.

docker-compose.yml

@@ -0,0 +1,54 @@
+services:
+  db:
+    image: postgres:15
+    environment:
+      POSTGRES_DB: ${POSTGRES_DB}
+      POSTGRES_USER: ${POSTGRES_USER}
+      POSTGRES_PASSWORD: ${POSTGRES_PASSWORD}
+    volumes:
+      - postgres_data:/var/lib/postgresql/data
+    ports:
+      - "${POSTGRES_PORT:-5432}:5432"
+    healthcheck:
+      test: ["CMD-SHELL", "pg_isready -U ${POSTGRES_USER}"]
+      interval: 10s
+      timeout: 5s
+      retries: 5
+
+  pgadmin:
+    image: dpage/pgadmin4:latest
+    environment:
+      PGADMIN_DEFAULT_EMAIL: ${PGADMIN_EMAIL}
+      PGADMIN_DEFAULT_PASSWORD: ${PGADMIN_PASSWORD}
+    ports:
+      - "${PGADMIN_PORT:-5050}:80"
+    depends_on:
+      - db
+    volumes:
+      - pgadmin_data:/var/lib/pgadmin
+
+  timetrack:
+    build: .
+    environment:
+      FLASK_ENV: ${FLASK_ENV:-production}
+      SECRET_KEY: ${SECRET_KEY}
+      DATABASE_URL: postgresql://${POSTGRES_USER}:${POSTGRES_PASSWORD}@db:5432/${POSTGRES_DB}
+      MAIL_SERVER: ${MAIL_SERVER}
+      MAIL_PORT: ${MAIL_PORT}
+      MAIL_USE_TLS: ${MAIL_USE_TLS}
+      MAIL_USERNAME: ${MAIL_USERNAME}
+      MAIL_PASSWORD: ${MAIL_PASSWORD}
+      MAIL_DEFAULT_SENDER: ${MAIL_DEFAULT_SENDER}
+    ports:
+      - "${TIMETRACK_PORT:-5000}:5000"
+    depends_on:
+      db:
+        condition: service_healthy
+    volumes:
+      - ${DATA_PATH:-./data}:/data
+      - shared_socket:/host/shared
+
+volumes:
+  postgres_data:
+  pgadmin_data:
+  shared_socket: