Make the Rust client the sole app

scripts/run-tests.sh

@@ -2,6 +2,6 @@
 # Extra arguments are forwarded to each workspace's `cargo test`.
 set -eu
 cd "$(dirname "$0")/.."
-for workspace in event-model server app-rust; do
+for workspace in event-model server app; do
   (cd "$workspace" && cargo test "$@")
 done