Make the Rust client the sole app

.gitignore

@@ -1,19 +1,6 @@
-.gradle/
-build/
-app/androidApp/build/
-app/shellApp/build/
-local.properties
-.kotlin/
-*.iml
-.idea/
-.DS_Store
 server/target/
 event-model/target/
-app-rust/target/
-
-# E3's native library, built by cargo-ndk straight into the Gradle module
-# (RUST.md) -- an artifact, like server/target/ above, not source.
-app/shellApp/src/main/jniLibs/
+app/target/
 
 # Server logs from a development run (ai-server.log by convention,
 # wg-test.log from ./test-wg-tunnel.sh).
@@ -32,8 +19,4 @@ sessions/
 # iris, the in-house UI library, is vendored at iris/ and built by cargo.
 iris/target/
 
-# The packaging xtask and the GPU rigs, both under scripts/. `build/`
-# above already covers scripts/build/outputs/apk, where `cargo xtask apk`
-# publishes for Dev Updater to find.
-scripts/xtask/target/
 scripts/rigs/gpu-probe/target/