Initial commit: Star of Words Unity project

Snapshot of the existing Unity 6 language-learning word game before any
refactoring. Adds Unity .gitignore and .gitattributes.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

ProjectSettings/PackageManagerSettings.asset

@@ -0,0 +1,44 @@
+%YAML 1.1
+%TAG !u! tag:unity3d.com,2011:
+--- !u!114 &1
+MonoBehaviour:
+  m_ObjectHideFlags: 53
+  m_CorrespondingSourceObject: {fileID: 0}
+  m_PrefabInstance: {fileID: 0}
+  m_PrefabAsset: {fileID: 0}
+  m_GameObject: {fileID: 0}
+  m_Enabled: 1
+  m_EditorHideFlags: 0
+  m_Script: {fileID: 13964, guid: 0000000000000000e000000000000000, type: 0}
+  m_Name: 
+  m_EditorClassIdentifier: UnityEditor.dll::UnityEditor.PackageManager.UI.Internal.PackageManagerProjectSettings
+  m_EnablePreReleasePackages: 0
+  m_AdvancedSettingsExpanded: 1
+  m_ScopedRegistriesSettingsExpanded: 1
+  m_SeeAllPackageVersions: 0
+  m_DismissPreviewPackagesInUse: 0
+  oneTimeWarningShown: 0
+  oneTimePackageErrorsPopUpShown: 0
+  m_MainRegistry:
+    m_Id: main
+    m_Name: 
+    m_Url: https://packages.unity.com
+    m_Scopes: []
+    m_IsDefault: 1
+    m_IsUnityRegistry: 1
+    m_Capabilities: 7
+    m_ConfigSource: 0
+    m_Compliance:
+      m_Status: 0
+      m_Violations: []
+  m_ScopedRegistries: []
+  m_UserSelectedRegistryName: 
+  m_UserAddingNewScopedRegistry: 0
+  m_RegistryInfoDraft:
+    m_Modified: 0
+    m_ErrorMessage: 
+    m_UserModificationsEntityId:
+      m_rawData: 568105589213756508
+    m_OriginalEntityId:
+      m_rawData: 568105589213756506
+  m_LoadAssets: 0