[Bug] Unable to modify effort setting when settings.json managed by NixOS/home-manager

Bug Description
When settings.json is created by nixos / home-manager, it's impossible to change effort. However, claude automatically adjusts itself to xhigh, and one can not turn it down then...

Environment Info

• Platform: linux
• Terminal: kitty
• Version: 2.1.119
• Feedback ID: 698cb91b-7627-4505-b83a-5dcf842c8f6d

Errors

[{"error":"Error: Plugin component file not found: /home/data/.claude/plugins/cache/claude-plugins-official/stagehand/0.1.0/.claude/skills/browser-automation for stagehand\n    at tEK (/$bunfs/root/src/entrypoints/cli.js:1135:15534)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-05-02T02:13:56.045Z"},{"error":"Error: Failed to read raw settings from /home/data/.claude/settings.json: Error: EACCES: permission denied, open '/nix/store/wkj1iqpcrpyrkcdsimcg9val2k408wk9-home-manager-files/.claude/settings.json'\n    at k6 (/$bunfs/root/src/entrypoints/cli.js:195:79)\n    at QF7 (/$bunfs/root/src/entrypoints/cli.js:5564:2339)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-05-02T02:13:57.280Z"}]