Port of upstream grok-build 1.0.4/1.0.5. Two paths read $HOME only,
which is usually unset on Windows outside Git Bash:
- the global-gitignore fallback (prompt/ignore.rs) now uses
std::env::home_dir(), the crate-wide idiom;
- fast-worktree's resolve_kigi_home falls back to std::env::home_dir()
with the same dunce canonicalization, eliminating the documented
divergence from kigi_config::default_kigi_home. On Unix home_dir()
reads $HOME first, so behavior is unchanged where HOME is set.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01KSy9S31pZNWXtRZNVJ1sDf
ZacharyZhang-NYandClaude Fable 5
574122884a