Add vendor .deb package to packages/

Includes crash-cart.deb (Linux-X64 Crash Cart Software_1240415.deb) so the
Docker image can be built without needing to source the file separately.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

.gitignore

@@ -1,3 +1,2 @@
-# The .deb package is large and proprietary — don't commit it
-packages/*.deb
+# RPM not used (Ubuntu-based container uses the .deb)
 packages/*.rpm