feat(blog): back blog module with central Directus CMS

Blog posts now live in the shared Directus instance (Coolify / Süper Panel
project) instead of the per-env blog_posts table, so prod and staging serve
identical content. API response shape is unchanged; Redis list cache and the
n8n automation endpoint keep working as before.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

docker-compose.coolify.yml

@@ -100,6 +100,14 @@ services:
       # memory: catalog-wide bridge had 7-114x noise; only add a catalog once
       # its per-vehicle bridge is wired & OEM-verified.
       - EMEX_SOURCE_DB_ALLOWED_CATALOGS=${EMEX_SOURCE_DB_ALLOWED_CATALOGS:-}
+      # Central Directus CMS (Süper Panel project on Coolify). Prod and staging
+      # point at the SAME instance so blog content is shared across envs.
+      # Internal docker-network URL — both stacks join the `coolify` network.
+      - DIRECTUS_URL=${DIRECTUS_URL:-}
+      - DIRECTUS_TOKEN=${DIRECTUS_TOKEN:-}
+      - DIRECTUS_PROJECT=${DIRECTUS_PROJECT:-sase}
+      # Bearer token for POST /blog/posts/internal (Süper Panel n8n pipeline)
+      - BLOG_AUTOMATION_TOKEN=${BLOG_AUTOMATION_TOKEN:-}
     depends_on:
       sase-redis:
         condition: service_healthy