Initial commit: Unity Needle AR Menu project with MenuScene and SampleScene web apps

Add root .gitignore for Unity Library/Temp/Logs, IDE folders, and node_modules.
Include Assets, Needle TypeScript (MenuController, asset picker, WebXR), and project configuration.

Made-with: Cursor

ProjectSettings/EditorBuildSettings.asset

@@ -0,0 +1,12 @@
+%YAML 1.1
+%TAG !u! tag:unity3d.com,2011:
+--- !u!1045 &1
+EditorBuildSettings:
+  m_ObjectHideFlags: 0
+  serializedVersion: 2
+  m_Scenes:
+  - enabled: 1
+    path: Assets/Scenes/SampleScene.unity
+    guid: 99c9720ab356a0642a771bea13969a05
+  m_configObjects:
+    com.unity.input.settings.actions: {fileID: -944628639613478452, guid: 052faaac586de48259a63d0c4782560b, type: 3}