feat(landing): add /features USP page with ratings and comparison

Adds a comprehensive features page listing all 12 USPs of the Mana
platform with usefulness ratings (3-5 stars), detail bullet points,
and a cost comparison section (Mana vs individual tools). Also fixes
a devlog content schema error (category 'fix' -> 'bugfix') and adds
a footer link to the new page.

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

apps/mana/apps/landing/src/components/navigation/Footer.astro

@@ -34,6 +34,7 @@ const platformLinks = [
 	{ label: 'Dashboard', href: 'https://mana.how' },
 	{ label: 'Observatory', href: 'https://mana.how/observatory' },
 	{ label: 'Alle Apps', href: '/apps' },
+	{ label: 'Features', href: '/features' },
 	{ label: 'Preise', href: '/pricing' },
 ];
 

apps/mana/apps/landing/src/content/devlog/2026-04-04-mana-media-cas-effect-depth-fix.md

@@ -3,7 +3,7 @@ title: 'mana-media als zentrale Bild-Pipeline + Effect-Depth-Fix'
 description: 'Kurzer Tag: Bild-Uploads aller 5 Module routen über mana-media (CAS, Thumbnails, EXIF, Photos-Galerie). Dazu der Fix für effect_update_depth_exceeded der seit dem Unified-App-Switch auf 6 Dashboard-Modulen heumkroch.'
 date: 2026-04-04
 author: 'Till Schneider'
-category: 'fix'
+category: 'bugfix'
 tags:
   ['mana-media', 'cas', 'thumbnails', 'photos', 'svelte5', 'reactivity', 'liveQuery', 'guest-mode']
 featured: false