🔒 Fix insecure release signing configuration

.gitignore

@@ -11,3 +11,4 @@ local.properties
 .jules
 .kotlin
 .log
+keystore.properties

app/build.gradle.kts

@@ -1,3 +1,6 @@
+import java.io.FileInputStream
+import java.util.Properties
+
 plugins {
     alias(libs.plugins.android.application)
     alias(libs.plugins.kotlin.android)
@@ -21,14 +24,36 @@ android {
         testInstrumentationRunner = "androidx.test.runner.AndroidJUnitRunner"
     }
 
+    val keystorePropertiesFile = rootProject.file("keystore.properties")
+    val hasKeystore = keystorePropertiesFile.exists()
+
+    signingConfigs {
+        if (hasKeystore) {
+            create("release") {
+                val properties = Properties()
+                properties.load(FileInputStream(keystorePropertiesFile))
+
+                keyAlias = properties.getProperty("keyAlias")
+                keyPassword = properties.getProperty("keyPassword")
+                val storeFileName = properties.getProperty("storeFile")
+                if (storeFileName != null) {
+                    storeFile = keystorePropertiesFile.parentFile.resolve(storeFileName.toString())
+                }
+                storePassword = properties.getProperty("storePassword")
+            }
+        }
+    }
+
     buildTypes {
         release {
             isMinifyEnabled = false
             proguardFiles(
                 getDefaultProguardFile("proguard-android-optimize.txt"),
                 "proguard-rules.pro"
             )
-            signingConfig = signingConfigs.getByName("debug")
+            if (hasKeystore) {
+                signingConfig = signingConfigs.getByName("release")
+            }
         }
         debug {
             isMinifyEnabled = false

keystore.properties.example

@@ -0,0 +1,4 @@
+keyAlias=my-key-alias
+keyPassword=my-key-password
+storeFile=my-upload-key.keystore
+storePassword=my-store-password