chore(prod): support .env.docker in crons, fix WAL mapping and add canvas copy in Dockerfile

scripts/backup/verify-backups.sh

@@ -1,6 +1,13 @@
 #!/bin/bash
 set -euo pipefail
 
+# Load environment variables from .env.docker if it exists
+if [ -f "/opt/memento/.env.docker" ]; then
+  set -a
+  source "/opt/memento/.env.docker"
+  set +a
+fi
+
 BACKUP_DIR="/opt/memento/backups"
 SNAPSHOT_DIR="$BACKUP_DIR/snapshots"
 PG_CONTAINER="memento-postgres"