Revert "Deployment Redesign"

This reverts commit 764d087eac.

.env.infra.example

@@ -1,5 +1,20 @@
-# Shared infrastructure config. Copy to `.env.infra`; the real file is
-# ignored by git and is also read by scripts/create-business.sh.
-MYSQL_ROOT_PASSWORD="replace-with-a-long-random-password"
-# Optional loopback-only port for an SSH tunnel or local admin tool.
-MYSQL_HOST_PORT=127.0.0.1:3306
+# Shared infrastructure config — see docker-compose.infra.yaml for the
+# full setup sequence. Copy this to `.env.infra` (kept out of git — see
+# .gitignore) and fill in real values.
+#
+#   docker network create next-chair-edge
+#   docker compose -f docker-compose.infra.yaml --env-file .env.infra up -d
+
+# ── MySQL (shared server — one database per business, created manually
+# per business, see docker-compose.infra.yaml's own header) ────────────
+MYSQL_ROOT_PASSWORD="replace-me"
+# Host-machine port MySQL is reachable on, e.g. for a GUI client over an
+# SSH tunnel — every business's app container always reaches it via the
+# shared Docker network and the service name `next-chair-mysql`, never
+# this.
+MYSQL_HOST_PORT=3306
+
+# ── Traefik (reverse proxy + automatic TLS via Let's Encrypt) ──────────
+# Let's Encrypt sends renewal/expiry notices here — use a real address
+# you actually check, not a placeholder.
+ACME_EMAIL="you@example.com"