fix: add sleep to vsock probe retry loop in proxy script

vsock-connect --probe returns instantly on connection refused, so the
wait loop burned through all iterations in ~2s instead of 30s. Add a
0.2s sleep between attempts so the first VM launch has time to boot.

modules/scripts.nix

@@ -235,17 +235,20 @@ let
       VMNAME="${vm.name}"
       PORT=5000
       TIMEOUT=30
-      ELAPSED=0
+      INTERVAL=0.2
+      MAX_ATTEMPTS=$((TIMEOUT * 5))  # TIMEOUT / INTERVAL
+      ATTEMPT=0
 
       # Wait for vsock to become available
-      while [ $ELAPSED -lt $TIMEOUT ]; do
+      while [ $ATTEMPT -lt $MAX_ATTEMPTS ]; do
         if ${vsockConnect} --timeout 0.5 --probe "$VMNAME" "$PORT" 2>/dev/null; then
           break
         fi
-        ELAPSED=$((ELAPSED + 1))
+        sleep $INTERVAL
+        ATTEMPT=$((ATTEMPT + 1))
       done
 
-      if [ $ELAPSED -ge $TIMEOUT ]; then
+      if [ $ATTEMPT -ge $MAX_ATTEMPTS ]; then
         echo "Timeout waiting for VM ${vm.name} vsock:$PORT" >&2
         exit 1
       fi