account data only; integrate smtp server; logging

smtp/smtp.go

@@ -0,0 +1,13 @@
+package smtp
+
+import (
+	"context"
+
+	"maunium.net/go/mautrix/id"
+)
+
+// Client interface to send emails
+type Client interface {
+	GetMappings(context.Context) (map[string]id.RoomID, error)
+	Send(from, to, subject, body string) error
+}