Auto-format markup in CI

Use xmlfmt with some extra post-processing since xmlfmt has a few
issues wrt extra newlines.

.build.yml

@@ -1,9 +1,13 @@
 ---
+# we rsync binaries.tar.gz from the same server we deploy to.
+# it contains these static-pie binaries:
+# hugo, brotli, ect (like gzip/zopfli), sd, and xmlfmt.
 image: alpine/edge
 packages:
   - rsync
   - git  # for Hugo's gitInfo
   - bmake
+  - moreutils
 sources:
   - https://git.sr.ht/~seirdy/seirdy.one
 secrets:

layouts/partials/head.html

@@ -42,9 +42,6 @@
 	{{- end }}
 	{{ $icon_192 := resources.Get "/apple-touch-icon.png" | resources.Fingerprint "md5" }}
 	{{- printf `<link rel="icon" sizes="192x192" href="%s" type="image/png" />` $icon_192.RelPermalink | safeHTML -}}
-{{ $favicon := resources.Get "/favicon.png" -}}
-{{ $favicon_base64 := $favicon.Content | base64Encode }}
-{{ printf `<link rel="icon" sizes="32x32" href="data:image/png;base64,%s" type="image/png" />` $favicon_base64 | safeHTML }}
 	<meta name="color-scheme" content="light dark" />
 	<meta name="format-detection" content="telephone=no" /><!-- Why does apple do this -->
 	<meta name="theme-color" content="#111" media="(prefers-color-scheme:dark)" />

layouts/partials/webmentions.html

@@ -55,5 +55,5 @@
 			<dd>This post does not have any approved Webmentions yet.</dd>
 			{{- end }}
 		</dl>
-		<p></p>
+		<p>Feel free to contact me directly with feedback; <a href="{{ .Site.BaseURL }}about/#location-seirdy-online">here’s my contact info</a></p>
 	</section>

scripts/xhtmlize.sh

@@ -5,7 +5,8 @@
 # XML tooling.
 # this means that every index.html file has an equivalent index.xhtml file.
 # content negotiation allows an agent to pick html or xhtml.
+# echo "<?xml version=\"1.0\" encoding=\"UTF-8\"?>"
 
 find "$1" -type f -name '*.html' \
-	-exec sh -c 'echo "<?xml version=\"1.0\" encoding=\"UTF-8\"?>" | cat - "$0" | grep -Fv "<meta charset=\"UTF-8\" />" >"${0%*.html}.xhtml"' {} \;
+	-exec sh -c 'echo "<?xml version=\"1.0\" encoding=\"UTF-8\"?>" >"${0%*.html}.xhtml" && xmlfmt -i "	" -f "$0" | busybox sed -e :a -e "/./,\$!d;/^\n*\$/{\$d;N;};/\n\$/ba" | sd -f m "\n(?:\t*)?</" "</" | sd -f m "<pre>\n\t*<code" "<pre><code" | pee "sed 5d >>\"${0%*.html}.xhtml\"" "sponge \"$0\""' {} \;
 # done