fix: use generated NitroDownloadResult type instead of internal structs

- Remove duplicate NitroDownloadResult definitions
- Use generated NitroDownloadResult from nitrogen on both platforms
- Fix return type mismatch in Android HybridNitroFS
- Fix return type mismatch in iOS HybridNitroFs

Author: patrickkabwe

android/src/main/java/com/nitrofs/FileDownloader.kt

@@ -1,6 +1,7 @@
 package com.nitrofs
 
 import android.util.Log
+import com.margelo.nitro.nitrofs.NitroDownloadResult
 import com.margelo.nitro.nitrofs.NitroFile
 import io.ktor.client.HttpClient
 import io.ktor.client.call.body
@@ -25,11 +26,6 @@ import java.util.UUID
 import java.util.concurrent.ConcurrentHashMap
 import java.io.File
 
-data class NitroDownloadResult(
-    val jobId: String,
-    val file: NitroFile
-)
-
 class FileDownloader {
     private val downloadScope = CoroutineScope(SupervisorJob() + Dispatchers.IO)
     private val downloadJobs = ConcurrentHashMap<String, Job>()

android/src/main/java/com/nitrofs/HybridNitroFS.kt

@@ -4,6 +4,7 @@ import android.util.Log
 import com.margelo.nitro.NitroModules
 import com.margelo.nitro.core.Promise
 import com.margelo.nitro.nitrofs.HybridNitroFSSpec
+import com.margelo.nitro.nitrofs.NitroDownloadResult
 import com.margelo.nitro.nitrofs.NitroFile
 import com.margelo.nitro.nitrofs.NitroFileEncoding
 import com.margelo.nitro.nitrofs.NitroFileStat
@@ -206,15 +207,10 @@ class HybridNitroFS: HybridNitroFSSpec() {
         serverUrl: String,
         destinationPath: String,
         onProgress: ((Double, Double) -> Unit)?
-    ): Promise<Map<String, Any>> {
+    ): Promise<NitroDownloadResult> {
         return Promise.async(ioScope) {
             try {
-                val result = nitroFsImpl.downloadFile(serverUrl, destinationPath, onProgress)
-                
-                return@async mapOf(
-                    "jobId" to result.jobId,
-                    "file" to result.file
-                )
+                nitroFsImpl.downloadFile(serverUrl, destinationPath, onProgress)
             } catch (e: Exception) {
                 Log.e(TAG, "Error downloading file: ${e.message}")
                 throw Error(e)

android/src/main/java/com/nitrofs/NitroFSImpl.kt

@@ -7,6 +7,7 @@ import android.provider.OpenableColumns
 import android.util.Log
 import android.webkit.MimeTypeMap
 import com.facebook.react.bridge.ReactApplicationContext
+import com.margelo.nitro.nitrofs.NitroDownloadResult
 import com.margelo.nitro.nitrofs.NitroFile
 import com.margelo.nitro.nitrofs.NitroFileEncoding
 import com.margelo.nitro.nitrofs.NitroFileStat

ios/HybridNitroFs.swift

@@ -181,19 +181,14 @@ class HybridNitroFS: HybridNitroFSSpec {
         }
     }
 
-    func downloadFile(serverUrl: String, destinationPath: String, onProgress: ((Double, Double) -> Void)?) throws -> NitroModules.Promise<[String: Any]> {
+    func downloadFile(serverUrl: String, destinationPath: String, onProgress: ((Double, Double) -> Void)?) throws -> NitroModules.Promise<NitroDownloadResult> {
         return .async { [unowned self] in
             do {
-                let result = try await self.nitroFSImpl.downloadFile(
+                return try await self.nitroFSImpl.downloadFile(
                     serverUrl: serverUrl,
                     destinationPath: destinationPath,
                     onProgress: onProgress
                 )
-                
-                return [
-                    "jobId": result.jobId,
-                    "file": result.file
-                ]
             } catch {
                 os_log("failed to download file: \(error.localizedDescription)")
                 throw error

ios/NitroFSFileDownloader.swift

@@ -6,11 +6,7 @@
 //
 
 import Foundation
-
-struct NitroDownloadResult {
-    let jobId: String
-    let file: NitroFile
-}
+import NitroModules
 
 final class NitroFSFileDownloader: NSObject {
     private weak var fileManager: FileManager?

ios/NitroFSImpl.swift

@@ -6,6 +6,7 @@
 //
 
 import Foundation
+import NitroModules
 import os
 
 class NitroFSImpl {