remove vim-plug, use native vim packages for copilot

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

.local/bin/git-orphan

@@ -1,7 +0,0 @@
-#!/bin/bash
-git checkout --orphan temp
-git add -A
-git commit -m "init"
-git branch -D main
-git branch -m temp main
-git push -f origin main

.local/bin/git-orphan

@@ -0,0 +1 @@
+/Users/syui/dotfiles/.local/bin/git-orphan