show preimage on tx modal for outgoing payment

[grunch]

Description

When the user pays an invoice needs to know the preimage as a proof of payment, currently it's not showing this field on transaction detail modal.

Steps to reproduce the behavior

Pay an invoice, go to transactions, click on the transaction you just made

Expected behavior

Show the preimage to the user, I prefer to use "Proof of payment" because it's explains to user the importance of this number.

Actual behavior

Doesn't show the preimage

Screenshot

It would look something like this

[grunch]

I made a PR for this, let me know if is ok

https://github.com/lightninglabs/lightning-app/pull/495

[tanx]

@grunch thanks for the PR. We'll discuss internally if we wanna surface the pre-image as the payment hash is already displayed as the ID.

[juscamarena]

Need this already...

As a merchant I already have a user telling me he paid and I don't see it on our end paying from a lightning labs wallet.

He showed the payment hash but that's not proof of anything.

Now accusing us of stealing money. https://www.reddit.com/r/Bitrefill/comments/c6dnco/did_bitrefill_steal_my_money/

[juscamarena]

Nice: https://github.com/lightninglabs/lightning-app/pull/1165

When will this be in a release? I can point the user of ours that way.