Staff-ship streaming edit file tool (#50720)

Release Notes:

- N/A

crates/feature_flags/src/flags.rs

@@ -69,6 +69,6 @@ impl FeatureFlag for StreamingEditFileToolFeatureFlag {
     const NAME: &'static str = "streaming-edit-file-tool";
 
     fn enabled_for_staff() -> bool {
-        false
+        true
     }
 }