refactor: rename nutriphi module to food (Essen)

Complete rename across the entire monorepo pre-launch:
- Module, routes, API, i18n, standalone landing app directories
- All code identifiers, display names, logo component
- German user-facing label: "Essen" (English brand stays "Food")
- Dexie table nutriFavorites -> foodFavorites
- Infra configs (docker-compose, cloudflared, nginx, wrangler)

Zero residue of nutriphi remains. No data migration needed (pre-launch).

Follow-up: run pnpm install, update Cloudflare DNS
(food.mana.how), rename Cloudflare Pages project.

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

cloudflared-config.yml

@@ -62,7 +62,7 @@ ingress:
     service: http://localhost:5000
   - hostname: presi.mana.how
     service: http://localhost:5000
-  - hostname: nutriphi.mana.how
+  - hostname: food.mana.how
     service: http://localhost:5000
   - hostname: photos.mana.how
     service: http://localhost:5000