fix: improve transfer recognition and local data safety

frontend/android/app/build.gradle.kts

@@ -1,4 +1,5 @@
 import java.io.FileInputStream
+import java.net.URI
 import java.util.Base64
 import java.util.Properties
 
@@ -120,15 +121,21 @@ val internalReleaseRequested = gradle.startParameter.taskNames.any { requestedTa
     taskName.contains("InternalRelease", ignoreCase = true)
 }
 if (internalReleaseRequested) {
-    val expectedApiUrl = "https://lt.frp-say.com:38012"
     if (dartDefines["INTERNAL_BUILD"] != "true") {
         throw GradleException(
             "Internal release requires --dart-define=INTERNAL_BUILD=true",
         )
     }
-    if (dartDefines["API_BASE_URL"] != expectedApiUrl) {
+    val apiBaseUrl = dartDefines["API_BASE_URL"]?.trim().orEmpty()
+    val validApiBaseUrl = runCatching {
+        val uri = URI(apiBaseUrl)
+        uri.scheme in setOf("http", "https") &&
+            !uri.host.isNullOrBlank() &&
+            uri.userInfo == null
+    }.getOrDefault(false)
+    if (!validApiBaseUrl) {
         throw GradleException(
-            "Internal release requires --dart-define=API_BASE_URL=$expectedApiUrl",
+            "Internal release requires an explicit HTTP(S) --dart-define=API_BASE_URL=<url>",
         )
     }
     if (dartDefines["APP_VERSION"].isNullOrBlank()) {