sqldb+invoices: synchronize SQL invoice updater behavior with KV version

Previously SQL invoice updater ignored the set ID hint when updating an
AMP invoice resulting in update subscriptions returning all of the AMP
state as well as all AMP HTLCs. This commit synchornizes behavior with
the KV implementation such that we now only return relevant AMP state
and HTLCs when updating an AMP invoice.

sqldb/sqlc/queries/invoices.sql

@@ -26,7 +26,11 @@ WHERE invoice_id = $1;
 -- name: GetInvoice :many
 SELECT i.*
 FROM invoices i
-LEFT JOIN amp_sub_invoices a on i.id = a.invoice_id
+LEFT JOIN amp_sub_invoices a 
+ON i.id = a.invoice_id
+AND (
+    a.set_id = sqlc.narg('set_id') OR sqlc.narg('set_id') IS NULL
+)
 WHERE (
     i.id = sqlc.narg('add_index') OR 
     sqlc.narg('add_index') IS NULL
@@ -39,13 +43,16 @@ WHERE (
 ) AND (
     i.payment_addr = sqlc.narg('payment_addr') OR 
     sqlc.narg('payment_addr') IS NULL
-) AND (
-    a.set_id = sqlc.narg('set_id') OR
-    sqlc.narg('set_id') IS NULL
 )
 GROUP BY i.id
 LIMIT 2;
 
+-- name: GetInvoiceBySetID :many
+SELECT i.*
+FROM invoices i
+INNER JOIN amp_sub_invoices a 
+ON i.id = a.invoice_id AND a.set_id = $1;
+
 -- name: FilterInvoices :many
 SELECT
     invoices.*