fix: Correct create_scene argument passing and node ownership

[alienfrenZyNo1]

1. JSON Argument Passing on Windows:

   • Previously, JSON parameters passed as command-line arguments from the Node.js server (src/index.ts) to the Godot operations script (src/scripts/godot_operations.gd) were getting corrupted on Windows.
   • This was caused by using child_process.spawn with shell: true and attempting Unix-style shell escaping, which doesn't work correctly in Windows shells (cmd/powershell).
   • Fix: Modified executeOperation in src/index.ts to use spawn with shell: false. This allows Node.js to handle argument quoting correctly across platforms, and the raw JSON string can be passed directly without needing shell-specific escaping.

2. Godot Node Ownership Error:

   • After fixing the argument passing, the create_scene function in src/scripts/godot_operations.gd was failing with a Godot engine error: Condition "p_owner == this" is true.
   • This was caused by incorrectly setting scene_root.owner = scene_root before packing the scene.
   • Fix: Removed the scene_root.owner = scene_root line. The PackedScene.pack() method correctly handles the ownership of the root node being packed.

With these changes, the create_scene tool now functions correctly, successfully creating scene files as intended.