The [TGeoTrap class](https://root.cern.ch/doc/master/classTGeoTrap.html#a0e27ff95f2ffa2eb8c320a7778e1f403) (for which an object is created here) has a slightly different calling syntax than what is done internally in [G4Trap](https://apc.u-paris.fr/~franco/g4doxy/html/classG4Trap.html#074ca31710e0a11f9c7b6b13ddd1eabf). We need to take the atan here to get to the angle that TGeoTrap wants.

Remove using declarations in root-cling dictionary files to avoid interpreter clashes with the global namespace

Co-authored-by: Andre Sailer <andre.philippe.sailer@cern.ch>

Use of nicely named variables such as $p may clash with local user
environments. A similar change was implemented in ROOT a long time
ago:
https://github.com/root-project/root/commit/bba80a143655a4aac63cb5adb2e9f2d73bcd9566

Unknown pragma error