Add CF pages build script

cf_build.sh

@@ -0,0 +1,12 @@
+#!/bin/bash
+
+# Build script for deploying to Cloudflare Pages (https://community.cloudflare.com/t/different-build-commands-for-build-previews/266084)
+
+if [ "$CF_PAGES_BRANCH" == "gh-pages" ]; then
+  # Just copy the output into the site/ dir on gh-pages (already built by mike)
+  mkdir site/
+  ls | grep -v "site" | xargs -n1 mv -t site
+else
+  # Else run mkdocs build to compile in Poetry venv
+  poetry run mkdocs build
+fi