Add shop, POS sync, event ticketing, and shipping catalog apps.

Clients can run in-house retail without Shopify while keeping the same
Docker/Django/Postgres stack and data-ownership promise. Closes #5.

scripts/validate-env.sh

@@ -82,6 +82,41 @@ if _true "${FEATURE_SOCIAL_AI:-}"; then
     exit 1
   fi
 fi
+if _true "${FEATURE_SHOP:-}"; then
+  if ! _true "${FEATURE_EMAIL_SMS:-}"; then
+    echo "FEATURE_SHOP requires FEATURE_EMAIL_SMS" >&2
+    exit 1
+  fi
+  if ! _true "${FEATURE_PAYMENTS:-}"; then
+    echo "FEATURE_SHOP requires FEATURE_PAYMENTS" >&2
+    exit 1
+  fi
+fi
+if _true "${FEATURE_POS_SYNC:-}"; then
+  if ! _true "${FEATURE_SHOP:-}"; then
+    echo "FEATURE_POS_SYNC requires FEATURE_SHOP" >&2
+    exit 1
+  fi
+  if [[ "$DJANGO_ENV" == "prod" || "$DJANGO_ENV" == "beta" ]]; then
+    required_vars+=(POS_WEBHOOK_SECRET)
+  fi
+fi
+if _true "${FEATURE_EVENTS:-}"; then
+  if ! _true "${FEATURE_EMAIL_SMS:-}"; then
+    echo "FEATURE_EVENTS requires FEATURE_EMAIL_SMS" >&2
+    exit 1
+  fi
+  if ! _true "${FEATURE_PAYMENTS:-}"; then
+    echo "FEATURE_EVENTS requires FEATURE_PAYMENTS" >&2
+    exit 1
+  fi
+fi
+if _true "${FEATURE_SHIPPING:-}"; then
+  if ! _true "${FEATURE_SHOP:-}"; then
+    echo "FEATURE_SHIPPING requires FEATURE_SHOP" >&2
+    exit 1
+  fi
+fi
 
 missing=()
 for var in "${required_vars[@]}"; do