feat(analytics): pull pm86 site-id from CMS page_config, drop env var

- +layout.server: expose pageConfig.analyticsPm86SiteId on layout data
- +layout.svelte: inject analytics.pm86.de script when CMS value present
- +error.svelte: light 404 page with wald-700 accent, dropped dark gradient
- .env.example + deploy.yml: remove PUBLIC_ANALYTICS_PM86_SITE_ID

.gitea/workflows/deploy.yml

@@ -14,7 +14,6 @@
 #   ORIGIN                         https://www.windwiderstand.de
 #   REVALIDATE_TOKEN               openssl rand -hex 32
 #   PUBLIC_UMAMI_WEBSITE_ID        (optional, sonst leer)
-#   PUBLIC_ANALYTICS_PM86_SITE_ID  (optional, sonst leer)
 
 name: Deploy
 
@@ -86,7 +85,6 @@ jobs:
           IMAGE_CACHE_DIR=/data/image-cache
           PUBLIC_UMAMI_SCRIPT_URL=https://cloud.umami.is/script.js
           PUBLIC_UMAMI_WEBSITE_ID=${{ secrets.PUBLIC_UMAMI_WEBSITE_ID }}
-          PUBLIC_ANALYTICS_PM86_SITE_ID=${{ secrets.PUBLIC_ANALYTICS_PM86_SITE_ID }}
           ENVEOF
 
       - name: Pull and restart container