Add skew to localizer visualization

Not using it for filtering yet, but this makes a filter easy to add.

Signed-off-by: milind-u <milind.upadhyay@gmail.com>
Change-Id: Ib0f052ee9cd709d1e5065e284830a9f6d94172f0
diff --git a/y2023/localizer/visualization.fbs b/y2023/localizer/visualization.fbs
index 9c9c648..8fa03f0 100644
--- a/y2023/localizer/visualization.fbs
+++ b/y2023/localizer/visualization.fbs
@@ -25,6 +25,8 @@
   correction_x: double (id: 12);
   correction_y: double (id: 13);
   correction_theta: double (id: 14);
+  // The angle between the camera axis and target normal.
+  skew:double (id: 15);
 }
 
 table Visualization {