Make the Rust client the sole app

app/android-project/app/build.gradle

@@ -0,0 +1,63 @@
+plugins {
+    id("com.android.application")
+}
+
+// build-apk.sh places the Rust cdylib in src/main/jniLibs before Gradle runs.
+def benchBuild = System.getenv("AI_APP_BENCH") == "1"
+
+android {
+    namespace = "dev.iris.android.demo"
+    compileSdk = 37
+
+    defaultConfig {
+        applicationId = "com.example.aiapp"
+        // 29, not 26: `iris::android::view`'s touch handler dates each
+        // sample with `MotionEvent.getEventTimeNanos` and
+        // `getHistoricalEventTimeNanos`, both API 29, and a missing JNI
+        // method there is a hard crash on the first touch rather than a
+        // degraded fling. Raised deliberately rather than guarded at
+        // runtime: nothing this app is built for runs below 29, and an
+        // untested fallback path is its own defect. `build-apk.sh`'s
+        // `cargo ndk -P` is kept at the same number.
+        minSdk = 29
+        // targetSdk 35+ supplies real IME overlap under enforced edge-to-edge.
+        targetSdk = 37
+        versionCode = 1
+        versionName = "1.0"
+        manifestPlaceholders = [appLabel: benchBuild ? "AI Sessions bench" : "AI Sessions"]
+    }
+
+    // The signing key is machine-local; build-apk.sh creates and supplies it.
+    def keystore = System.getenv("AI_APP_KEYSTORE")
+    signingConfigs {
+        if (keystore != null) {
+            release {
+                storeFile = file(keystore)
+                storePassword = System.getenv("AI_APP_KEYSTORE_PASSWORD")
+                keyAlias = "ai-app"
+                keyPassword = storePassword
+            }
+        }
+    }
+
+    buildTypes {
+        debug {
+            if (benchBuild) {
+                applicationIdSuffix ".bench"
+            }
+        }
+        release {
+            if (benchBuild) {
+                applicationIdSuffix ".bench"
+            }
+            if (keystore != null) {
+                signingConfig = signingConfigs.release
+            }
+        }
+    }
+
+    compileOptions {
+        sourceCompatibility = JavaVersion.VERSION_17
+        targetCompatibility = JavaVersion.VERSION_17
+    }
+}