fix binary/artifact-in-docker errors and uncertainties

readme.txt

@@ -0,0 +1,8 @@
+arche
+=====
+
+Regarding /web/styles.css
+
+    The styles.css file, which is generated by a standalone Tailwind binary downloaded and executed automatically within build.rs, is to be committed any time it changes, as without it styling will be broken on the frontend part of the page.
+
+    This is in contrast to a perhaps expected approach of gitignoring them and just generating them every build; this is incompatible with building docker images in an efficient way, however, as docker exposes no way to mount directories while retaining ability to write files and execute binaries.