Use Starlette, uvicorn and websockets; rename Docker files to container ones

Serve neo4j-browser with Starlette and uvicorn (the optional browser extra)
instead of a hand-written HTTP server, and handle Bolt over WebSocket with the
websockets library's Sans-I/O protocol. Rename Dockerfile, .dockerignore and
docker/ to Containerfile, .containerignore and container/.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

THIRD_PARTY_NOTICES.md

@@ -1,7 +1,7 @@
 # Third-party notices
 
-peo's own code (the `peo/`, `docker/` and `tests/` directories, the
-`Dockerfile` and `pyproject.toml`) is licensed under the GNU General Public
+peo's own code (the `peo/`, `container/` and `tests/` directories, the
+`Containerfile` and `pyproject.toml`) is licensed under the GNU General Public
 License v3.0 or later; see [LICENSE](LICENSE).
 
 The container image built from this repository also contains the third-party
@@ -11,11 +11,12 @@ the image is built. Inside the image, license texts are collected under
 
 | Component | License | Copyright | License text in the image |
 | --- | --- | --- | --- |
-| [neo4j-browser](https://github.com/neo4j/neo4j-browser), built unmodified from the commit pinned in the `Dockerfile` | GPL-3.0-or-later | Neo4j Sweden AB | `/usr/share/doc/peo/neo4j-browser/` (`LICENSE`, `NOTICE.txt`) |
+| [neo4j-browser](https://github.com/neo4j/neo4j-browser), built unmodified from the commit pinned in the `Containerfile` | GPL-3.0-or-later | Neo4j Sweden AB | `/usr/share/doc/peo/neo4j-browser/` (`LICENSE`, `NOTICE.txt`) |
 | JavaScript libraries bundled into neo4j-browser | various (MIT, Apache-2.0, BSD, ...) | their respective authors | `/usr/share/doc/peo/neo4j-browser/LICENSES.txt` |
 | [Apache AGE](https://github.com/apache/age), from the `apache/age` base image | Apache-2.0 | The Apache Software Foundation; portions Bitnine Co., Ltd. | `/usr/share/doc/peo/apache-age/` (`LICENSE`, `NOTICE`) |
 | [PostgreSQL](https://www.postgresql.org/), from the `apache/age` base image | PostgreSQL License | The PostgreSQL Global Development Group, The Regents of the University of California | `/usr/share/doc/postgresql-18/copyright` |
 | Debian GNU/Linux base system and packages, including Python 3 and `python3-psycopg` (LGPL-3.0) | various | their respective authors | `/usr/share/doc/<package>/copyright` |
+| Python packages peo depends on, installed from PyPI: `websockets` (BSD-3-Clause), `starlette` (BSD-3-Clause), `uvicorn` (BSD-3-Clause) and their dependencies | various (BSD-3-Clause, MIT, PSF-2.0) | their respective authors | `*.dist-info/` under `/opt/peo/venv/lib/python3*/site-packages/`, or `/usr/share/doc/peo/peo-python-licenses/` for packages whose wheel lacks a license file |
 | [pgAdmin 4](https://www.pgadmin.org/), installed from PyPI | PostgreSQL License | The pgAdmin Development Team | `/opt/pgadmin/app/LICENSE` |
 | Python packages pgAdmin depends on, and `gunicorn` (MIT) | various | their respective authors | `*.dist-info/` under `/opt/pgadmin/lib/python3*/site-packages/`, or `/usr/share/doc/peo/pgadmin-python-licenses/` for packages whose wheel lacks a license file |
 
@@ -26,9 +27,10 @@ the image is built. Inside the image, license texts are collected under
   it as `/usr/share/doc/peo/neo4j-browser/neo4j-browser-source.tar.gz`, an
   archive of the exact commit that was built. Its dependencies are pinned by
   the `yarn.lock` inside that archive, and the build steps are in this
-  repository's `Dockerfile`.
+  repository's `Containerfile`.
 - **peo** itself ships as Python source code in the `/opt/peo/venv/`
-  virtual environment. This repository has the rest.
+  virtual environment, next to the Python packages it depends on. This
+  repository has the rest.
 - **Debian packages:** source is available from
   [sources.debian.org](https://sources.debian.org/) and the Debian archive.