fix: allow unsigned CI debug builds

android/app/build.gradle.kts

@@ -7,8 +7,8 @@ plugins {
     id("com.google.gms.google-services")
 }
 
-// Release signing is intentionally optional during configuration so debug/profile
-// builds (including GitHub Actions CI) do not require private signing credentials.
+// Release signing is optional during configuration so debug/profile builds
+// (including GitHub Actions CI) do not require private signing credentials.
 val keystoreProperties = Properties()
 val keystorePropertiesFile = rootProject.file("key.properties")
 
@@ -62,13 +62,9 @@ android {
 
     buildTypes {
         release {
-            val releaseSigningConfig = signingConfigs.findByName("release")
-                ?: throw GradleException(
-                    "Release signing is not configured. " +
-                        "Provide android/key.properties with storePassword, keyPassword, " +
-                        "keyAlias, and storeFile for a signed release build."
-                )
-            signingConfig = releaseSigningConfig
+            signingConfigs.findByName("release")?.let {
+                signingConfig = it
+            }
         }
     }
 }