DesignGate frontend/backend patches for Penpot 2.18.3

DesignGate is a modified build of Penpot 2.18.3 (https://github.com/penpot/penpot/tree/2.18.3),
Copyright (c) KALEIDOS INC, licensed under the Mozilla Public License 2.0
(https://www.mozilla.org/en-US/MPL/2.0/).

This archive contains every modification applied to the upstream release images:
  patch_frontend.py   - edits to the compiled frontend bundle (/var/www/app)
  patch_backend.py    - edits to email templates inside the backend jar
  Dockerfile.*        - how the upstream images are patched (pinned by digest)
  pins-frontend.sha256 - checksums of the upstream files the patch expects
  assets/             - DesignGate logo, favicon, CSS overrides, licenses page

The modifications to MPL-2.0 covered files are distributed under the MPL-2.0 as well.
To rebuild: docker build -f Dockerfile.frontend . ; docker build -f Dockerfile.backend .
