ci: separate docs into scripts

scripts/flatten-docs.sh

@@ -0,0 +1,21 @@
+#!/usr/bin/env bash
+# Flatten rustdoc output so the crate serves at the doc root rather than under
+# <crate>/. Moves the crate's pages up to the doc root and drops one ../ from
+# each page's references to the shared assets (CSS/JS, search index, source),
+# scaled to the page's depth.
+# Env: DOCROOT (default target/doc), CRATE (default coursebank).
+set -euo pipefail
+docroot="${DOCROOT:-target/doc}"
+crate="${CRATE:-coursebank}"
+[ -d "$docroot/$crate" ] || { echo "no $docroot/$crate; did you build the docs?" >&2; exit 1; }
+cp -a "$docroot/$crate/." "$docroot/"
+rm -rf "${docroot:?}/${crate:?}"
+resources='static\.files/\|crates\.js\|search-index\|search\.desc/\|src/\|settings\.html\|help\.html\|trait\.impl/\|type\.impl/'
+while IFS= read -r -d '' f; do
+  rel="${f#"$docroot"/}"
+  depth=$(printf '%s' "$rel" | tr -cd '/' | wc -c)
+  pat=''; for ((i=0; i<=depth; i++)); do pat="\\.\\./$pat"; done
+  rep=''; for ((i=0; i<depth;  i++)); do rep="../$rep"; done
+  sed -i "s#${pat}\(${resources}\)#${rep}\1#g" "$f"
+done < <(find "$docroot" -name '*.html' -print0)
+echo "flattened $crate into $docroot"