web: a failure names itself on the page (issue #167)

The Series list row's fact line gains the failure word and its age in one
mark before the Notes chips, spelled through outcomeWord — the one
vocabulary shared with the Lanes chips. The detail page adds one sentence
beside the correction control while a Reader's number stands behind a
failure past the owner window, without naming the Reader. Each Lanes Site
name is a plain link to that Site's failing Series; the outcome chips stay
unlinked, and outcomeChips records why the promise is withdrawn.

backend/internal/web/templates/lanes.html

@@ -26,7 +26,7 @@
     </div>
     {{range .Rows}}
     <div class="trow{{if .Attention}} attention{{end}}">
-      <span class="c-site">{{.Site}}</span>
+      <a class="c-site" href="{{.FailingHref}}">{{.Site}}</a>
       <span>{{.Due}}</span>
       <span>{{.Checked}}</span>
       <span>{{.Gap}}</span>