convert type array to array when triggering onDataChange

@lpatiny

Convert the type array to an array once exporting the data as .nmrium format or when triggering onDatachange call-back which is not the case in the current version.

```ts
{
"data": {
"x": {
"0": -8.890310912266614,
"1": -8.886940412367153,
"2": -8.883569912467664,
"3": -8.880199412568203,
"4": -8.876828912668714,
"5": -8.873458412769224,
"6": -8.870087912869764,
"7": -8.866717412970274,
"8": -8.863346913070814,
"9": -8.859976413171324,
"10": -8.856605913271835,
"11": -8.853235413372374,
"12": -8.849864913472885
},
re: { ...},
im: { ...}
}
}

```