chore(unity): 固定Unity CLI Loop本地包并移除UnitySkills依赖

Client/Packages/io.github.hatayama.uloopmcp/Editor/UI/CliInstallRefreshPolicy.cs

@@ -0,0 +1,10 @@
+namespace io.github.hatayama.uLoopMCP
+{
+    internal static class CliInstallRefreshPolicy
+    {
+        internal static bool ShouldRefreshSkillsAfterCliInstall(bool wasCliInstalledBeforeInstall)
+        {
+            return !wasCliInstalledBeforeInstall;
+        }
+    }
+}