🐛 fix: Add missing imports to build.gradle.kts for GitHub Actions

- Import java.util.Properties and java.io.FileInputStream
- Fix Gradle Kotlin DSL compilation errors
- Use getProperty() instead of casting to avoid warnings

android/app/build.gradle.kts

@@ -3,6 +3,9 @@ plugins {
     alias(libs.plugins.kotlin.android)
 }
 
+import java.util.Properties
+import java.io.FileInputStream
+
 android {
     namespace = "dev.dettmer.simplenotes"
     compileSdk {
@@ -35,13 +38,13 @@ android {
             // Load keystore configuration from key.properties file
             val keystorePropertiesFile = rootProject.file("key.properties")
             if (keystorePropertiesFile.exists()) {
-                val keystoreProperties = java.util.Properties()
-                keystoreProperties.load(java.io.FileInputStream(keystorePropertiesFile))
+                val keystoreProperties = Properties()
+                keystoreProperties.load(FileInputStream(keystorePropertiesFile))
                 
-                storeFile = file(keystoreProperties["storeFile"] as String)
-                storePassword = keystoreProperties["storePassword"] as String
-                keyAlias = keystoreProperties["keyAlias"] as String
-                keyPassword = keystoreProperties["keyPassword"] as String
+                storeFile = file(keystoreProperties.getProperty("storeFile"))
+                storePassword = keystoreProperties.getProperty("storePassword")
+                keyAlias = keystoreProperties.getProperty("keyAlias")
+                keyPassword = keystoreProperties.getProperty("keyPassword")
             }
         }
     }