Add release signing config and fix missing INTERNET permission

- Configure release signing via key.properties + Gradle Kotlin DSL
- Add INTERNET and ACCESS_NETWORK_STATE permissions to AndroidManifest
  (Flutter injects INTERNET automatically in debug builds but not release,
  causing DNS failures in sideloaded APKs)
- Restore android/.gitignore entries lost during signing setup
- Gitignore key.properties and fabled-release-key.jks

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

android/app/build.gradle.kts

@@ -1,3 +1,6 @@
+import java.io.FileInputStream
+import java.util.Properties
+
 plugins {
     id("com.android.application")
     id("kotlin-android")
@@ -5,6 +8,12 @@ plugins {
     id("dev.flutter.flutter-gradle-plugin")
 }
 
+val keystorePropertiesFile = rootProject.file("key.properties")
+val keystoreProperties = Properties()
+if (keystorePropertiesFile.exists()) {
+    keystoreProperties.load(FileInputStream(keystorePropertiesFile))
+}
+
 android {
     namespace = "com.fabledapp.fabled_app"
     compileSdk = flutter.compileSdkVersion
@@ -20,21 +29,29 @@ android {
     }
 
     defaultConfig {
-        // TODO: Specify your own unique Application ID (https://developer.android.com/studio/build/application-id.html).
         applicationId = "com.fabledapp.fabled_app"
-        // You can update the following values to match your application needs.
-        // For more information, see: https://flutter.dev/to/review-gradle-config.
         minSdk = flutter.minSdkVersion
         targetSdk = flutter.targetSdkVersion
         versionCode = flutter.versionCode
         versionName = flutter.versionName
     }
 
+    signingConfigs {
+        create("release") {
+            keyAlias = keystoreProperties["keyAlias"] as String
+            keyPassword = keystoreProperties["keyPassword"] as String
+            storeFile = file(keystoreProperties["storeFile"] as String)
+            storePassword = keystoreProperties["storePassword"] as String
+        }
+    }
+
     buildTypes {
         release {
-            // TODO: Add your own signing config for the release build.
-            // Signing with the debug keys for now, so `flutter run --release` works.
-            signingConfig = signingConfigs.getByName("debug")
+            signingConfig = if (keystorePropertiesFile.exists()) {
+                signingConfigs.getByName("release")
+            } else {
+                signingConfigs.getByName("debug")
+            }
         }
     }
 

android/app/src/main/AndroidManifest.xml

@@ -1,4 +1,6 @@
 <manifest xmlns:android="http://schemas.android.com/apk/res/android">
+    <uses-permission android:name="android.permission.INTERNET"/>
+    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
     <uses-permission android:name="android.permission.REQUEST_INSTALL_PACKAGES" />
 
     <application