add env_vars nobuild

mealie/config.yaml

@@ -85,6 +85,7 @@ map:
   - ssl:rw
 name: Mealie
 options:
+  env_vars: []
   ALLOW_SIGNUP: true
   DATA_DIR: /config
   PGID: 1000
@@ -99,6 +100,9 @@ ports:
 ports_description:
   9001/tcp: Web interface
 schema:
+  env_vars:
+    - name: match(^[A-Z0-9_]+$)
+      value: str?
   ALLOW_SIGNUP: bool
   BASE_URL: str?
   DATA_DIR: str?