Restructured lektor project for simpler builds

.gitignore

@@ -1,2 +1,3 @@
 public/
+lektor/lektordata/output/
 .DS_Store

lektor/docker/Dockerfile

@@ -3,6 +3,8 @@ FROM debian:latest
 RUN apt update
 RUN apt install -y python3-pip python3-venv pipx
 RUN pipx install lektor
-RUN mkdir /opt/lektor
-WORKDIR /opt/lektor
+RUN mkdir -p /opt/lektor/project && mkdir -p /opt/lektor/output
+
+WORKDIR /opt/lektor/project
+
 ENV PATH="$PATH:/root/.local/bin"