Add BOLT12 support to bLIP-51 / LSPS1

[tnull]

Previously, bLIP-51 / LSPS1 only supported BOLT11 and onchain payment options. Here we add the necessary fields to allow to pay the LSP via BOLT12 offers.

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[TheBlueMatt]

I imagine there's a part 2 to this where the messages get used somehow?

[tnull]

I imagine there's a part 2 to this where the messages get used somehow?

Yes, we'll just add support for it when we finally add LSPS1 service side. On the client side we simply expose LSPS1PaymentInfo to the user as they need to choose their preferred payment method.

I now realized I missed adding the actual bolt12 field on LSPS1PaymentInfo (and tests didn't catch it as serde ignores unknown fields by default). Now force-pushed the fix:

> git diff-tree -U2 7674b739d 3274dbf5a
diff --git a/lightning-liquidity/src/lsps1/msgs.rs b/lightning-liquidity/src/lsps1/msgs.rs
index 7a4366ff7..0d9a6cec2 100644
--- a/lightning-liquidity/src/lsps1/msgs.rs
+++ b/lightning-liquidity/src/lsps1/msgs.rs
@@ -153,4 +153,6 @@ pub struct LSPS1PaymentInfo {
        /// A Lightning payment using BOLT 11.
        pub bolt11: Option<LSPS1Bolt11PaymentInfo>,
+       /// A Lightning payment using BOLT 12.
+       pub bolt12: Option<LSPS1Bolt12PaymentInfo>,
        /// An onchain payment.
        pub onchain: Option<LSPS1OnchainPaymentInfo>,
@@ -452,5 +454,8 @@ mod tests {
                        }
                }"#;
-               let _payment: LSPS1PaymentInfo = serde_json::from_str(json_str).unwrap();
+               let payment: LSPS1PaymentInfo = serde_json::from_str(json_str).unwrap();
+               assert!(payment.bolt11.is_some());
+               assert!(payment.bolt12.is_some());
+               assert!(payment.onchain.is_some());

                let json_str = r#"{
@@ -493,6 +498,9 @@ mod tests {
                        "channel": null
                }"#;
-               let _create_order_response: LSPS1CreateOrderResponse =
+               let create_order_response: LSPS1CreateOrderResponse =
                        serde_json::from_str(json_str).unwrap();
+               assert!(create_order_response.payment.bolt11.is_some());
+               assert!(create_order_response.payment.bolt12.is_some());
+               assert!(create_order_response.payment.onchain.is_some());

                let json_str = r#"{

[arik-so]

thanks for the bolt12 field check addition!

[tnull]

thanks for the bolt12 field check addition!

Sure! Going to land this, as ~trivial and the diff to previously-ACKed version is minimal.