Bug: The manage_scene screenshot action reports saving to Assets/Screenshots/filename.png but actually saves to the project root folder

Cause: In ScreenshotUtility.CaptureToAssetsFolder(), only the filename was passed to ScreenCapture.CaptureScreenshot():

  string captureName = Path.GetFileName(normalizedFullPath);  // "filename.png"
  ScreenCapture.CaptureScreenshot(captureName, size);         // Saves to project root

Fix: Pass the project-relative path instead of just the filename:

ScreenCapture.CaptureScreenshot(assetsRelativePath, size); // "Assets/Screenshots/filename.png"

File: MCPForUnity/Runtime/Helpers/ScreenshotUtility.cs (lines 42-52)

Note: Only affects Play Mode screenshots. Edit Mode captures using CaptureFromCameraToAssetsFolder() were already working correctly since they use File.WriteAllBytes() with the full path.