Improved README and ui-asset workflow

pkgs/ui/nix/update-ui-assets.sh

@@ -3,8 +3,17 @@ set -xeuo pipefail
 
 # GITEA_TOKEN
 if [[ -z "${GITEA_TOKEN:-}" ]]; then
-  echo "GITEA_TOKEN is not set"
-  echo "Go to https://gitea.gchq.icu/user/settings/applications and generate a token"
+  echo "GITEA_TOKEN is not set. Check if the secret BOT_ACCESS_TOKEN is set in the repository settings."
+  exit 1
+fi
+
+if [[ -z "${BOT_NAME:-}" ]]; then
+  echo "Env var BOT_NAME is not set. Use the name of the bot user here."
+  exit 1
+fi
+
+if [[ -z "${GITHUB_SERVER_URL:-}" ]]; then
+  echo "Env var GITHUB_SERVER_URL is not set. Please use the Gitea base URL here."
   exit 1
 fi
 
@@ -22,11 +31,12 @@ nix build '.#ui' --out-link "$tmpdir/result"
 tar --transform 's,^\.,assets,' -czvf "$tmpdir/assets.tar.gz" -C "$tmpdir"/result/lib/node_modules/*/out .
 NAR_HASH=$(nix-prefetch-url --unpack file://<(cat "$tmpdir/assets.tar.gz"))
 
-owner=ui-asset-bot
+owner=$BOT_NAME
 package_name=ui
 package_version=$NAR_HASH
+baseurl=$GITHUB_SERVER_URL
 
-url="https://gitea.gchq.icu/api/packages/$owner/generic/$package_name/$package_version/assets.tar.gz"
+url="$baseurl/api/packages/$owner/generic/$package_name/$package_version/assets.tar.gz"
 set +x
 curl --upload-file "$tmpdir/assets.tar.gz" -X PUT "$url?token=$GITEA_TOKEN"
 set -x