Consolidate nginx docs and scripts, update paths

TODO.md

@@ -1,4 +1,9 @@
-# TODO
-
-- [x] Remove random HSL gradients from homepage cards and use header's background gradient
-- [ ] Review other gradient usages (check if any leftover random hue generation anywhere)
+- [x] Analyze nginx/docs and nginx/scripts for deduplication opportunities
+- [x] Deduplicate nginx documentation files (removed DEPLOYMENT_COMPLETE.md, DEPLOY_NOW.md)
+- [x] Remove duplicate scripts (deploy-production.sh, deploy-production-new.sh, manage-admin-users.sh)
+- [x] Update justfile with new script paths
+- [x] Update top-level README.md
+- [x] Update nginx/README.md
+- [x] Create nginx/SETUP.md
+- [x] Create top-level SETUP.md
+- [x] Update documentation paths (/var/www/html/ → /var/www/posterg/, /formulaire/ → /admin/)