HrmpChannels: StorageDescriptor<[Key: {
recipient: number;
sender: number;
}], {
max_capacity: number;
max_message_size: number;
max_total_size: number;
mqc_head?: FixedSizeBinary<32>;
msg_count: number;
recipient_deposit: bigint;
sender_deposit: bigint;
total_size: number;
}, true, never>
HRMP channel data associated with each para. Invariant:
Paras::is_valid_para(P)
within a session.