- Set ZSH_THEME="" since powerlevel10k overrides it anyway
- Guard powerlevel10k, brew plugins, and atuin with existence checks
- Cache brew --prefix to avoid duplicate subprocess calls
- Strip ~80 lines of oh-my-zsh default boilerplate comments
- Replace hardcoded /Users/anton/ with $HOME in LM Studio PATH
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>