chore : rename Coltura to Starseed

- Rename project name across code, configs, docs, dev/prod infra
- Dev: DOCKER_APP_NAME + POSTGRES_DB switched to starseed, containers become php-starseed-fpm / nginx-starseed / starseed-db-1
- Dev: mount nginx.conf on default.conf instead of starseed.conf to avoid alphabetical-order clash with image's default site
- Makefile: export CURRENT_UID/CURRENT_GID at top level so docker compose builds (db-reset etc.) get them
- Prod: image registry path, container_name, volumes, vhost server_name + paths, DATABASE_URL, CORS, CI workflow
- Add doc/prompt-rename-prod.md with the migration runbook for the prod server (DB rename, FS move, vhost, Let's Encrypt)

infra/prod/deploy.sh

@@ -4,9 +4,9 @@ set -euo pipefail
 cd "$(dirname "$0")"
 
 TAG="${1:-latest}"
-export COLTURA_IMAGE_TAG="$TAG"
+export STARSEED_IMAGE_TAG="$TAG"
 
-echo "==> Deploying coltura:${TAG}..."
+echo "==> Deploying starseed:${TAG}..."
 
 echo "==> Enabling maintenance mode..."
 touch maintenance.on