Require a complete PCM return address before placing orders.

Empty PCM_RETURN_ADDRESS was sending SITE_NAME as firstName with blank street fields, which PCM rejects with 400; validate early and wire PCM env through compose.

docker-compose.yml

@@ -45,6 +45,19 @@ services:
       EMAIL_BACKEND: ${EMAIL_BACKEND:-django.core.mail.backends.console.EmailBackend}
       SMTP2GO_SMS_API_KEY: ${SMTP2GO_SMS_API_KEY:-}
       SMTP2GO_WEBHOOK_SECRET: ${SMTP2GO_WEBHOOK_SECRET:-}
+      POSTCARD_PROVIDER: ${POSTCARD_PROVIDER:-pcm}
+      PCM_API_KEY: ${PCM_API_KEY:-}
+      PCM_API_SECRET: ${PCM_API_SECRET:-}
+      PCM_CHILD_REF_NBR: ${PCM_CHILD_REF_NBR:-}
+      PCM_WEBHOOK_SECRETS: ${PCM_WEBHOOK_SECRETS:-}
+      PCM_WEBHOOK_SECRET: ${PCM_WEBHOOK_SECRET:-}
+      # Quote JSON in `.env`: PCM_RETURN_ADDRESS='{"firstName":"…",...}'
+      PCM_RETURN_ADDRESS: ${PCM_RETURN_ADDRESS:-}
+      PCM_RETURN_LINE1: ${PCM_RETURN_LINE1:-}
+      PCM_RETURN_LINE2: ${PCM_RETURN_LINE2:-}
+      PCM_RETURN_CITY: ${PCM_RETURN_CITY:-}
+      PCM_RETURN_STATE: ${PCM_RETURN_STATE:-}
+      PCM_RETURN_ZIP: ${PCM_RETURN_ZIP:-}
     depends_on:
       db:
         condition: service_healthy
@@ -70,6 +83,18 @@ services:
       EMAIL_BACKEND: ${EMAIL_BACKEND:-django.core.mail.backends.console.EmailBackend}
       SMTP2GO_SMS_API_KEY: ${SMTP2GO_SMS_API_KEY:-}
       SMTP2GO_WEBHOOK_SECRET: ${SMTP2GO_WEBHOOK_SECRET:-}
+      POSTCARD_PROVIDER: ${POSTCARD_PROVIDER:-pcm}
+      PCM_API_KEY: ${PCM_API_KEY:-}
+      PCM_API_SECRET: ${PCM_API_SECRET:-}
+      PCM_CHILD_REF_NBR: ${PCM_CHILD_REF_NBR:-}
+      PCM_WEBHOOK_SECRETS: ${PCM_WEBHOOK_SECRETS:-}
+      PCM_WEBHOOK_SECRET: ${PCM_WEBHOOK_SECRET:-}
+      PCM_RETURN_ADDRESS: ${PCM_RETURN_ADDRESS:-}
+      PCM_RETURN_LINE1: ${PCM_RETURN_LINE1:-}
+      PCM_RETURN_LINE2: ${PCM_RETURN_LINE2:-}
+      PCM_RETURN_CITY: ${PCM_RETURN_CITY:-}
+      PCM_RETURN_STATE: ${PCM_RETURN_STATE:-}
+      PCM_RETURN_ZIP: ${PCM_RETURN_ZIP:-}
     depends_on:
       db:
         condition: service_healthy