✨(widgets) import widgets code from Messages and setup Docker workflow (#33)

This adds Gaufre v2 with source, documentation, examples and built artefacts.
Also includes the feedback widget from Messages.

website/Dockerfile

@@ -0,0 +1,10 @@
+FROM node:22-slim AS website-deps
+
+WORKDIR /home/website/
+
+RUN npm install -g npm@11.3.0 && npm cache clean -f
+
+ARG DOCKER_USER
+USER ${DOCKER_USER}
+
+ENV npm_config_cache=/tmp/npm-cache