feat(rss): полный текст и обложки в RSS-ленте, лимит 5 постов

- hugo.toml: ShowFullTextinRSS=true, [services.RSS] limit=5
- тема rDedInit rss.xml: prepend cover (figure.entry-cover, absURL) в content:encoded
- openspec change rss-full-feed (план A реализован)

themes/rDedInit/layouts/_default/rss.xml

@@ -74,7 +74,14 @@
       <guid>{{ .Permalink }}</guid>
       <description>{{ with .Description | html }}{{ . }}{{ else }}{{ .Summary | html }}{{ end -}}</description>
       {{- if and site.Params.ShowFullTextinRSS .Content }}
-      <content:encoded>{{ (printf "<![CDATA[%s]]>" .Content) | safeHTML }}</content:encoded>
+      {{- $page := . }}
+      {{- $coverHtml := "" }}
+      {{- with .Params.cover.image }}
+        {{- $coverAbs := (path.Join $page.RelPermalink .) | absURL }}
+        {{- $coverAlt := ($page.Params.cover.alt | default $page.Title) | htmlEscape }}
+        {{- $coverHtml = printf "<figure class=\"entry-cover\"><img src=\"%s\" alt=\"%s\"></figure>" $coverAbs $coverAlt }}
+      {{- end }}
+      <content:encoded>{{ (printf "<![CDATA[%s%s]]>" $coverHtml .Content) | safeHTML }}</content:encoded>
       {{- end }}
     </item>
     {{- end }}