chore: create bundle version synchronizer script

Author: alp-kurt

Assets/Editor/SyncBundleVersion.cs

@@ -0,0 +1,42 @@
+#if UNITY_EDITOR
+using UnityEditor;
+using UnityEditor.Build;
+using UnityEditor.Build.Reporting;
+using System.IO;
+
+public class SyncBundleVersionPreprocess : IPreprocessBuildWithReport
+{
+    /// <summary>
+    /// Determines the order in which build preprocessors are called.
+    /// 0 means default/early execution.
+    /// </summary>
+    public int callbackOrder => 0;
+
+    /// <summary>
+    /// Keeps Unity's internal application version (Application.version) 
+    /// in sync with CI/CD-managed versions.
+    /// </summary>
+    public void OnPreprocessBuild(BuildReport report)
+    {
+        var versionPath = Path.Combine(Directory.GetCurrentDirectory(), "version.txt");
+        if (File.Exists(versionPath))
+        {
+            // Read the file and trim extra whitespace/newlines
+            var v = File.ReadAllText(versionPath).Trim();
+
+            // Update if the file is not empty and differs from current bundleVersion
+            if (!string.IsNullOrEmpty(v) && UnityEditor.PlayerSettings.bundleVersion != v)
+            {
+                UnityEditor.PlayerSettings.bundleVersion = v;   // Update Unity's app version
+
+                AssetDatabase.SaveAssets();
+                UnityEngine.Debug.Log($"[Build] Synced PlayerSettings.bundleVersion -> {v}");
+            }
+        }
+        else
+        {
+            UnityEngine.Debug.LogWarning("[Build] version.txt not found; bundleVersion not changed.");
+        }
+    }
+}
+#endif