Refactoring of the prototype data app

Switch to using TimeZoneDistro code to read the
distro_version file using TimeZoneDistro rather than
duplicating the information in the manifest.

Fixed the name of the asset containing the distro
for simplicity.

Added proguard.cfg to strip unnecesary code from the
new static library dependency.

Removed dependency on internal Streams class.

Test: Manual testing
Bug: 31008728
Change-Id: I5da659ae8208c5e430078d0b056ba0dc75944c1f