Clean up static variables in scripted beacon

Convert them to class variables to make it re-entrant.
Add additional logs.
Add output path for default scripted beacon.

Test: boot cuttlefish and check logcat
Tag: #gd-refactor
Bug: 154491371
Bug: 158019041
Change-Id: Id29cd38a2839976fa2975a3a505f93f2e2cb2b8d