feat: create basic Guild struct for Qord integration

Author: amatsagu

guild.go

@@ -0,0 +1,7 @@
+package tempest
+
+// https://discord.com/developers/docs/resources/guild#unavailable-guild-object
+type UnavailableGuild struct {
+	ID          Snowflake `json:"id"`
+	Unavailable bool      `json:"unavailable"`
+}