Use section _index.md titles in docs breadcrumbs instead of humanized URL slugs (#2290)

Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>

qdrant-landing/content/documentation/_index.md

@@ -1,5 +1,5 @@
 ---
-title: Home
+title: Documentation
 weight: 2
 hideTOC: true
 breadcrumb: false

qdrant-landing/themes/qdrant-2024/layouts/partials/documentation/breadcrumbs.html

@@ -5,7 +5,9 @@
   {{ range first $len $paths }}
     {{ if gt (len . ) 0 }}
       {{ $rellink = printf "%s/%s" $rellink . }}
-      <li class="docs-breadcrumbs__crumb"><a href="{{ $rellink }}/">{{ humanize . }}</a></li>
+      {{ $section := $.Site.GetPage $rellink }}
+      {{ $label := cond (ne $section nil) $section.Title (humanize .) }}
+      <li class="docs-breadcrumbs__crumb"><a href="{{ $rellink }}/">{{ $label }}</a></li>
       <li class="docs-breadcrumbs__crumb-separator"></li>
     {{ end }}
   {{ end }}