Allow multiple FoundationDB instances in the same process

tests/docker/scripts/init-fdb.sh

@@ -1,7 +1,18 @@
 #!/bin/bash
-set -e
+set -eu
 
-fdbcli --exec "configure new single memory"
-echo "FoundationDB configured."
-exit 0
+for i in $(seq 1 30); do
+    if fdbcli --exec 'status minimal' --timeout 5 2>&1 | grep -q "The database is available"; then
+        echo "FoundationDB already configured."
+        exit 0
+    fi
+    if fdbcli --exec 'configure new single memory' --timeout 5 2>&1 | grep -q "Database created"; then
+        echo "FoundationDB configured."
+        exit 0
+    fi
+    echo "Waiting for FoundationDB to be ready (attempt $i)..."
+    sleep 2
+done
 
+echo "ERROR: Failed to configure FoundationDB after retries" >&2
+exit 1