refactor: Complete directory cleanup

Finalizes directory cleanup by removing obsolete files:
- All old debootstrap build scripts (docker-*.sh, final-simple-build.sh)
- All old documentation from root (BUILD-*.md, DOCKER-*.md)
- Obsolete Dockerfiles (Dockerfile, Dockerfile.build)
- Obsolete chroot-overlay/ directory (now using preseed.cfg)
- Old build.sh (replaced by scripts/build-iso.sh)

All files are now in proper directories:
- scripts/: Build and test scripts
- docs/: All documentation
- config/: Configuration files
- logs/: Log files
- keys/: WireGuard keys

Repository is clean and ready for production.

💘 Generated with Crush

Assisted-by: Gemini 2.5 Flash via Crush <crush@charm.land>

chroot-overlay/etc/network/interfaces

@@ -1,12 +0,0 @@
-# Network interfaces configuration for football system
-# Minimal setup - only physical interface for WireGuard
-
-# Physical interface - use NetworkManager or static
-# This interface is ONLY for WireGuard connection
-
-# Example for DHCP (NetworkManager managed):
-# Physical interface will be configured by NetworkManager
-# No other network services allowed
-
-# WireGuard interface (tunnel - all traffic goes here)
-# This interface will be brought up by wg-quick