Disputes: StorageDescriptor<[number, FixedSizeBinary<32>], {
    concluded_at?: number;
    start: number;
    validators_against: {
        bitsLen: number;
        bytes: Uint8Array;
    };
    validators_for: {
        bitsLen: number;
        bytes: Uint8Array;
    };
}, true>

All ongoing or concluded disputes for the last several sessions.