feat: add stale bot config

Author: jsjoeio

.github/stale.yml

@@ -0,0 +1,12 @@
+# Number of days of inactivity before an issue becomes stale
+daysUntilStale: 180
+# Number of days of inactivity before a stale issue is closed
+daysUntilClose: 5
+# Label to apply when stale.
+staleLabel: stale
+# Comment to post when marking an issue as stale. Set to `false` to disable
+markComment: >
+  This issue has been automatically marked as stale because it has not had
+  recent activity. It will be closed if no activity occurs in the next 5 days.
+# Comment to post when closing a stale issue. Set to `false` to disable
+closeComment: false