Runway verifiable type

Summary:
Aniket and I chatted about creating a Runway verifiable type, since Runway needs a few specific things such as unique target grouping, calling relates, etc

This creates the verifiable type and matches the existing behavior

Because the scheduled job should be similar to a normal buck job, I have made a few things public. Without this, it is a lot of copy paste or missing metadata

Reviewed By: aniketmathur

Differential Revision: D59763484

fbshipit-source-id: e4e477de4ee2594662582c095915931ab95473eb

td_util/src/schedules.rs

@@ -122,7 +122,7 @@ pub enum ContinuousRunMode {
     OptHourly,
     OptEarlyAdoptor,
     OptAdhoc,
-    RunwayWWWShadow,
+    RunwayShadow,
 }
 
 #[cfg(test)]