Add Lightning Address payment and verification support

[Aniket-pd]

addressing token #221

This update introduces full Lightning Address support across the SDK. It adds verification and payment helpers to LightningService, along with new types and methods for handling the entire Lightning Address payment flow — including metadata parsing, invoice negotiation, and payment execution.

What's Included

• Lightning Address type definitions
  Defines LNURL-pay metadata, callback responses, and success actions.

• Extended LightningService helpers
  Adds reusable methods for verifying a Lightning Address and paying it through its negotiated invoice.

• Re-exported helper types
  Makes Lightning Address operations easier to access and use across the SDK.

[changeset-bot[bot]]

⚠️ No Changeset found

Latest commit: 249588a58044dc18a658edeb17ebc79c4937f42a

Merging this PR will not cause a version bump for any packages. If these changes should not result in a new version, you're good to go. If these changes should result in a version bump, you need to add a changeset.

This PR includes no changesets

When changesets are added to this PR, you'll see the packages that this PR includes changesets for and the associated semver types

Click here to learn what changesets are, and how to add one.

Click here if you're a maintainer who wants to add a changeset to this PR

[alexlwn123]

Hi @Aniket-pd! Thanks for the PR and welcome to the project.

Our rust client already contains much of the lnurl logic. It just needs to be exported. (see here)

So I think we can avoid rewriting the logic in JS.

cc: @MrImmortal09

[Aniket-pd]

Got it ,I’ll look into the section you linked and adjust the PR accordingly.

[Aniket-pd]

Thanks for flagging this. These SDK methods rely on two new LN RPCs (verify_lightning_address and pay_lightning_address) that aren’t in the current fedimint-client yet , they’re being added in a separate backend PR. I’ll update the changes in this PR once that backend PR is ready

[Aniket-pd]

Sorry for the misunderstanding , that was my mistake. I’ve opened a PR that adds the LN RPCs (verify_lightning_address and pay_lightning_address) to the fedimint-ln-client. Here’s the link to that PR: https://github.com/fedimint/fedimint/pull/7988