Add config plugin to persist release signing configuration

app.json

@@ -54,7 +54,8 @@
       ],
       "./plugins/withKioskAdmin",
       "./plugins/withUsbCamera",
-      "./plugins/withLocalAars"
+      "./plugins/withLocalAars",
+      "./withAndroidSigning"
     ],
     "extra": {
       "eas": {

withAndroidSigning.js

@@ -0,0 +1,37 @@
+const { withAppBuildGradle } = require('@expo/config-plugins');
+
+module.exports = function withAndroidSigning(config) {
+  return withAppBuildGradle(config, (config) => {
+    if (config.modResults.language === 'groovy') {
+      let buildGradle = config.modResults.contents;
+
+      const signingConfig = `
+        release {
+            if (project.hasProperty('SCHNAPPIX_RELEASE_STORE_FILE')) {
+                storeFile file("../../" + SCHNAPPIX_RELEASE_STORE_FILE)
+                storePassword SCHNAPPIX_RELEASE_STORE_PASSWORD
+                keyAlias SCHNAPPIX_RELEASE_KEY_ALIAS
+                keyPassword SCHNAPPIX_RELEASE_KEY_PASSWORD
+            }
+        }
+      `;
+      
+      if (!buildGradle.includes('SCHNAPPIX_RELEASE_STORE_FILE')) {
+          // Inject inside signingConfigs { ... }
+          buildGradle = buildGradle.replace(
+              /signingConfigs\s*\{([\s\S]*?)debug\s*\{([\s\S]*?)\}/,
+              `signingConfigs {$1debug {$2}\n${signingConfig}`
+          );
+
+          // Change buildTypes release to use signingConfigs.release
+          buildGradle = buildGradle.replace(
+              /signingConfig signingConfigs\.debug/g,
+              `signingConfig signingConfigs.release`
+          );
+      }
+
+      config.modResults.contents = buildGradle;
+    }
+    return config;
+  });
+};