Initial implementation of BLE-to-TCP serial bridge for Android

Android app that connects to a BLE UART device (Nordic UART Service by
default, matching RNode BLE) and exposes it as a TCP byte pipe, so socat
can present it to Reticulum as a serial port. Foreground service hosts a
GATT client with MTU negotiation, chunked serialized writes, and
auto-reconnect, plus a single-client last-wins TCP server. No root
required on either end.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

app/build.gradle.kts

@@ -0,0 +1,41 @@
+plugins {
+    id("com.android.application")
+    id("org.jetbrains.kotlin.android")
+}
+
+android {
+    namespace = "dev.wntrmute.bleserial"
+    compileSdk = 36
+
+    defaultConfig {
+        applicationId = "dev.wntrmute.bleserial"
+        minSdk = 26
+        targetSdk = 36
+        versionCode = 1
+        versionName = "0.1.0"
+    }
+
+    buildTypes {
+        release {
+            isMinifyEnabled = false
+        }
+    }
+
+    compileOptions {
+        sourceCompatibility = JavaVersion.VERSION_17
+        targetCompatibility = JavaVersion.VERSION_17
+    }
+
+    kotlinOptions {
+        jvmTarget = "17"
+    }
+}
+
+dependencies {
+    implementation("androidx.core:core-ktx:1.16.0")
+    implementation("androidx.appcompat:appcompat:1.7.1")
+    implementation("androidx.activity:activity-ktx:1.10.1")
+    implementation("androidx.lifecycle:lifecycle-runtime-ktx:2.9.0")
+    implementation("com.google.android.material:material:1.12.0")
+    implementation("org.jetbrains.kotlinx:kotlinx-coroutines-android:1.10.2")
+}