Curio A3

- Tore out and redid mid. Probably isnt perfect, but hopefully it's better.
- Moved some areas and routes closer together.
- Removed a bypass route to focus players a bit more.
- Some small changes to other routes and cover.
- Changed appearance of windows over intel to make it clearer they can be shot through.
- Added a window from one attackers' one-way route onto defenders' highground platform, to help attackers taking that route not have to dive in blind.
- Shortened respawn wave time for both teams to reduce downtime a bit.
- Re-added missing blu filter.
- Changed some door trigger sizes to be a touch less awkward.
- Made lockable oneways crush any unfortunate players standing there when they lock.
- Clipping improvements.

- Removed flank route that bypasses mid - nobody seemed to use it.
- Fixed borked logic! I'd messed it up while find-replacing when I copied the blu side over to the red side. Overtime and win calculation should now work reliably.
- Changed appearance of one-way doors to more clearly indicate direction and locking.
- Changed dropdown door behaviour to work properly with multiple players going down at once.
- Various geometry and texture changes.
- Fixed some symmetry inconsistencies.
- Added more clutter and detail.

- Areaportals have refused to cooperate so this version doesnt have the optimisation I wanted to give it. Hopefully will run okay regardless.