database: added keys migration, get/insert, insert keys at launch if none are present

crates/database/queries/keys/get_all.sql

@@ -0,0 +1,8 @@
+select id,
+       created_at as "created_at: DateTime<Utc>",
+       revoked_at as "revoked_at: DateTime<Utc>",
+       private_der,
+       public_der
+
+from keys
+order by created_at desc