Refactor Docker setup and migration scripts

- Updated Dockerfile to set permissions for the entrypoint script and defined the entrypoint for the container.
- Consolidated Alembic migration history into a single initial migration file and removed obsolete revision files.
- Added a new script to run Alembic migrations before starting the application.
- Updated changelog to reflect changes in migration handling and Docker setup.
- Enhanced pytest configuration for coverage reporting and excluded specific files from coverage calculations.

scripts/docker-entrypoint.sh

@@ -0,0 +1,9 @@
+#!/usr/bin/env sh
+set -e
+
+PYTHONPATH="/app:${PYTHONPATH}"
+export PYTHONPATH
+
+python -m scripts.run_migrations
+
+exec "$@"