We limit the number of concurrent blob downloads per node and per recovery, but if a user configures too many concurrent recoveries they may run out of per-node download permits which yields the following message:

> Unable to acquire permit to use snapshot files during recovery, this recovery will recover index files from the source node. Ensure snapshot files can be used during recovery by setting [indices.recovery.max_concurrent_snapshot_file_downloads] to be no greater than [25]

The `[25]` here is wrong, the 25 permits are shared across all inbound recoveries so we should divide the suggested value by `cluster.routing.allocation.node_concurrent_incoming_recoveries`. In extreme cases the user may have configured so many concurrent recoveries that the only reasonable limit is zero, and in that case we should suggest setting `indices.recovery.use_snapshots: false` instead.


server/src/main/java/org/elasticsearch/indices/recovery/RecoverySettings.java
() -> format(
                "using rate limit [%s] with [default=%s, read=%s, write=%s, max=%s]",
                finalMaxBytesPerSec,
                ofBytes(defaultBytesPerSec),
                ofBytes(readBytesPerSec),
                ofBytes(writeBytesPerSec),
                ofBytes(maxAllowedBytesPerSec)
            )
        );
        setMaxBytesPerSec(finalMaxBytesPerSec);
    }
    public RateLimiter rateLimiter() {
        return rateLimiter;
    }
    public TimeValue retryDelayNetwork() {
        return retryDelayNetwork;
    }
    public TimeValue retryDelayStateSync() {
        return retryDelayStateSync;
    }
    public TimeValue activityTimeout() {
        return activityTimeout;
    }
    public TimeValue internalActionTimeout() {
        return internalActionTimeout;
    }
    public TimeValue internalActionRetryTimeout() {
        return internalActionRetryTimeout;
    }
    public TimeValue internalActionLongTimeout() {