License peo4c under GPL-3.0-or-later and ship third-party notices

- Add the GPL-3.0 LICENSE and SPDX headers to peo4c's own files.
- Add THIRD_PARTY_NOTICES.md listing every bundled component, its
  license and where its license text lives in the image, plus a
  trademark disclaimer; reference it from the README.
- Ship neo4j-browser's LICENSE, NOTICE.txt and LICENSES.txt with a
  source archive of the built commit, as the GPL requires.
- Ship Apache AGE's LICENSE and NOTICE, which the base image lacks.
- Collect license texts for Python packages whose wheels omit them,
  from PyPI sdists or vendored copies in docker/licenses/.

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

docker/licenses/dnspython/LICENSE

@@ -0,0 +1,35 @@
+ISC License
+
+Copyright (C) Dnspython Contributors
+
+Permission to use, copy, modify, and/or distribute this software for
+any purpose with or without fee is hereby granted, provided that the
+above copyright notice and this permission notice appear in all
+copies.
+
+THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL
+WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE
+AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
+DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
+PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
+TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+PERFORMANCE OF THIS SOFTWARE.
+
+
+
+Copyright (C) 2001-2017 Nominum, Inc.
+Copyright (C) Google Inc.
+
+Permission to use, copy, modify, and distribute this software and its
+documentation for any purpose with or without fee is hereby granted,
+provided that the above copyright notice and this permission notice
+appear in all copies.
+
+THE SOFTWARE IS PROVIDED "AS IS" AND NOMINUM DISCLAIMS ALL WARRANTIES
+WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL NOMINUM BE LIABLE FOR
+ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
+OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.