Major apt-ostree refactor: Simplified architecture, Debian Trixie compatibility

- ✅ Successfully compiled with apt-pkg-native for Debian Trixie compatibility
- ✅ Replaced rust-apt with apt-pkg-native to resolve C++ standard issues
- ✅ Simplified project structure: removed unused binaries, focused on core functionality
- ✅ Basic commands working: help, list, search, info
- ✅ Created apt_compat.rs compatibility layer
- ✅ Updated debian packaging for libapt-pkg7.0 compatibility
- ✅ Removed complex dependencies and simplified main.rs
- 🎯 Next: Implement core package management commands (install, remove, upgrade)
- 🎯 Architecture: Ready for atomic package management with OSTree integration

debian/control

@@ -13,7 +13,8 @@ Build-Depends: debhelper (>= 13),
                libssl-dev,
                libsystemd-dev,
                libmount-dev,
-               libselinux1-dev
+               libselinux1-dev,
+               libapt-pkg-dev (>= 3.0.0)
 Standards-Version: 4.6.2
 Homepage: https://github.com/robojerk/apt-ostree
 Vcs-Git: https://github.com/robojerk/apt-ostree.git
@@ -25,7 +26,8 @@ Depends: ${shlibs:Depends},
          ${misc:Depends},
          libostree-1-1 (>= 2025.2),
          ostree,
-         systemd
+         systemd,
+         libapt-pkg7.0 (>= 3.0.0)
 Description: Debian/Ubuntu equivalent of rpm-ostree
  apt-ostree is a tool for managing atomic, immutable deployments
  on Debian and Ubuntu systems using OSTree as the backend.