Add release signing, fix release build, update README

- Configure release signing via environment variables (android-signing-env)
- Enable BuildConfig generation and guard HttpLoggingInterceptor to debug only
- Move okhttp.logging to implementation so release build compiles
- Update README: add E2EE, verification, push notifications, download link

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

app/build.gradle.kts

@@ -18,6 +18,16 @@ android {
         versionName = "0.1.0"
     }
 
+    signingConfigs {
+        create("release") {
+            storeFile = file(System.getenv("ANDROID_KEYSTORE_PATH") ?: "")
+            storeType = System.getenv("ANDROID_KEYSTORE_TYPE") ?: "PKCS12"
+            keyAlias = System.getenv("ANDROID_KEY_ALIAS") ?: ""
+            storePassword = System.getenv("ANDROID_KEYSTORE_PASSWORD") ?: ""
+            keyPassword = System.getenv("ANDROID_KEY_PASSWORD") ?: ""
+        }
+    }
+
     buildTypes {
         release {
             isMinifyEnabled = true
@@ -25,6 +35,7 @@ android {
                 getDefaultProguardFile("proguard-android-optimize.txt"),
                 "proguard-rules.pro"
             )
+            signingConfig = signingConfigs.getByName("release")
         }
     }
 
@@ -39,6 +50,7 @@ android {
 
     buildFeatures {
         compose = true
+        buildConfig = true
     }
 
     packaging {
@@ -68,5 +80,5 @@ dependencies {
     implementation(platform(libs.firebase.bom))
     implementation(libs.firebase.messaging)
     debugImplementation(libs.androidx.ui.tooling)
-    debugImplementation(libs.okhttp.logging)
+    implementation(libs.okhttp.logging)
 }

app/src/main/java/com/ltadeu6/matrix/matrix/MatrixSession.kt

@@ -25,7 +25,8 @@ import android.util.Log
 import okhttp3.MediaType.Companion.toMediaType
 import okhttp3.OkHttpClient
 import okhttp3.Request
-import okhttp3.logging.HttpLoggingInterceptor
+import com.ltadeu6.matrix.BuildConfig
+import okhttp3.Interceptor
 import retrofit2.Retrofit
 import java.util.concurrent.TimeUnit
 import java.util.concurrent.atomic.AtomicInteger
@@ -1331,12 +1332,16 @@ class MatrixSession private constructor(private val appContext: Context) {
     }
 
     private fun buildApi(homeserver: String) {
-        val logging = HttpLoggingInterceptor().apply { level = HttpLoggingInterceptor.Level.BODY }
-        val client = OkHttpClient.Builder()
+        val clientBuilder = OkHttpClient.Builder()
             .connectTimeout(30, TimeUnit.SECONDS)
             .readTimeout(60, TimeUnit.SECONDS)
-            .addInterceptor(logging)
-            .build()
+        if (BuildConfig.DEBUG) {
+            val logging = okhttp3.logging.HttpLoggingInterceptor().apply {
+                level = okhttp3.logging.HttpLoggingInterceptor.Level.BODY
+            }
+            clientBuilder.addInterceptor(logging)
+        }
+        val client = clientBuilder.build()
         api = Retrofit.Builder()
             .baseUrl(homeserver)
             .client(client)