Only run if there is no built flag

.ddev/commands/web/app

@@ -14,6 +14,7 @@ case $1 in
   install)
     drush site:install -y --account-pass=admin123 --existing-config
     drush user:login
+    touch .flag-built
     ;;
 
   refresh)

.ddev/config.yaml

@@ -11,8 +11,8 @@ additional_fqdns: []
 provider: default
 hooks:
   post-start:
-  - composer: install
-  - exec-host: ddev theme development
+  - exec: "[[ ! -f .flag-built ]] && composer install || exit 0"
+  - exec-host: "[[ ! -f .flag-built ]] && ddev theme development || exit 0"
   post-import-db:
   - exec: drush sql-sanitize -y --sanitize-password=password
   - exec: drush cr