style: enhance Congo theme — profile layout, richer homepage, author info

- Switch to profile homepage layout with author headline and bio
- Richer homepage content with topic overview (EN/DE)
- Show taxonomies on articles and lists
- Configure header, footer, scroll-to-top
- Remove theme attribution from footer

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

config/_default/params.toml

@@ -1,9 +1,20 @@
 colorScheme = "avocado"
 defaultAppearance = "light"
 autoSwitchAppearance = false
+mainSections = [""]
+
+[header]
+  layout = "basic"
+  showTitle = true
+
+[footer]
+  showCopyright = true
+  showThemeAttribution = false
+  showScrollToTop = true
+  showAppearanceSwitcher = false
 
 [homepage]
-  layout = "page"
+  layout = "profile"
   showRecent = true
   recentLimit = 5
 
@@ -13,6 +24,11 @@ autoSwitchAppearance = false
   showAuthor = true
   showBreadcrumbs = true
   showTableOfContents = true
+  showTaxonomies = true
 
 [list]
   showBreadcrumbs = true
+  showTaxonomies = true
+
+[taxonomy]
+  showTermCount = true