Add transaction_id field to SEP-12 requests

[CassioMG]

Also improves typing by adding a separate CustomerBinaryInfoMap type only for the binary (Buffer) fields.

Closes: Add transaction id to SEP-12 requests

[Ifropc]

How does passing Buffer vs passing a string will work?
My question, is how exactly both of this types will be included in the request?
Can we add a unit test that makes sure that the body layout is correct (I believe type of binary fields should NOT be text/plain) when passing either string or buffer
And in the future add an integration test with Anchor Platform to pass any of binary fields?

(I see we currently have tests with Polaris testanchor but it might just ignore this fields, so I don't think it's a very trustworthy test)

[CassioMG]

@Ifropc thanks for the review!
This is how it currently works: any string field should be passed through the sep9Info object and any binary field (e.g. KYC images) should be passed through the sep9BinaryInfo object.
If you pass any field on the sep9BinaryInfo object then the request Content-Type header will be set to multipart/form-data.

How does that sound?

[Ifropc]

I was a bit confused by

export type CustomerBinaryInfoMap = {
  [key: string]: Buffer | string;
};

My guess is that it will have an appropriate body layout depending on the type of the value in the map?
In any case, adding a unit test would be a great addition.

[CassioMG]

I was a bit confused by

export type CustomerBinaryInfoMap = {
  [key: string]: Buffer | string;
};

Fixed this is: 6f38db4

Now the types look like this:

export type CustomerInfoMap = {
  [key: string]: string;
};

export type CustomerBinaryInfoMap = {
  [key: string]: Buffer;
};

My guess is that it will have an appropriate body layout depending on the type of the value in the map?
In any case, adding a unit test would be a great addition.

Created a task to tackle this unit test: https://github.com/orgs/stellar/projects/58/views/1?pane=issue&itemId=78332363

[Ifropc]

LGTM, thanks for clarifying comment