DragonX SDK: increase batch size and update server endpoints

- Increase DOWNLOAD_BATCH_SIZE from 50 to 500 for faster sync
- Update default server endpoints to dragonx.is (mainnet and testnet)
- Add jniLibs source dir for Rust native libraries in build config

sdk-lib/build.gradle.kts

@@ -74,6 +74,7 @@ android {
     sourceSets.getByName("main") {
         java.srcDir("build/generated/source/grpc")
         proto { srcDir("src/main/proto") }
+        jniLibs.srcDir("build/rustJniLibs/android")
     }
 
     kotlinOptions {
@@ -293,6 +294,8 @@ project.afterEvaluate {
     val cargoTask = tasks.getByName("cargoBuild")
     tasks.getByName("javaPreCompileDebug").dependsOn(cargoTask)
     tasks.getByName("javaPreCompileRelease").dependsOn(cargoTask)
+    tasks.getByName("mergeDebugJniLibFolders").dependsOn(cargoTask)
+    tasks.getByName("mergeReleaseJniLibFolders").dependsOn(cargoTask)
 }
 
 fun MinimalExternalModuleDependency.asCoordinateString() =