chore: migrate internal and keysend columns to be non null

Author: im-adithya

db/migrations/20231030140000_invoice_internal.up.sql

@@ -0,0 +1,6 @@
+UPDATE invoices
+SET internal = false
+WHERE internal IS NULL;
+
+ALTER TABLE invoices
+ALTER COLUMN internal SET NOT NULL;

db/migrations/20231030140000_invoice_keysend.up.sql

@@ -0,0 +1,6 @@
+UPDATE invoices
+SET keysend = false
+WHERE keysend IS NULL;
+
+ALTER TABLE invoices
+ALTER COLUMN keysend SET NOT NULL;

db/models/invoice.go

@@ -22,8 +22,8 @@ type Invoice struct {
 	DestinationCustomRecords map[uint64][]byte `json:"custom_records,omitempty"`
 	RHash                    string            `json:"r_hash"`
 	Preimage                 string            `json:"preimage" bun:",nullzero"`
-	Internal                 bool              `json:"-" bun:",nullzero"`
-	Keysend                  bool              `json:"keysend" bun:",nullzero"`
+	Internal                 bool              `json:"-" bun:",notnull"`
+	Keysend                  bool              `json:"keysend" bun:",notnull"`
 	State                    string            `json:"state" bun:",default:'initialized'"`
 	ErrorMessage             string            `json:"error_message,omitempty" bun:",nullzero"`
 	AddIndex                 uint64            `json:"-" bun:",nullzero"`