Drop ineffective ~/.config/git read exception

Project settings can't re-open a path denied by another settings source,
so this lives in user settings instead.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

.claude/settings.json

@@ -47,9 +47,6 @@
       "denyWrite": [
         ".claude/settings.json",
         ".claude/settings.local.json"
-      ],
-      "allowRead": [
-        "~/.config/git"
       ]
     },
     "network": {