[Bug] Header border not rendered when CWD is ~/Documents (v2.1.110 regression)

Description

The header box border (╭─╮) is not rendered when running claude from ~/Documents. This is a regression introduced in v2.1.110 — v2.1.109 renders the border correctly in the same directory.

Reproduction

cd ~/Documents && claude
# Header border missing

Expected

Header renders with box border like in all other directories.

Debugging performed

| Test | Border? |
|------|---------|
| ~/Documents (even completely empty) | ❌ |
| ~/Documents/any-subfolder | ✅ |
| ~/Downloads | ✅ |
| ~/Desktop | ✅ |
| ~ (home) | ✅ |
| /tmp/* | ✅ |
| Symlink to ~/Documents from /tmp | ❌ |
| v2.1.109 in ~/Documents | ✅ |

Ruled out

• Terminal encoding (ko_KR.UTF-8, box-drawing chars render fine via echo)
• Font (box chars display correctly)
• NO_COLOR=1 — no change
• CLAUDE_CODE_NO_FLICKER — no change
• File contents — issue persists with completely empty ~/Documents
• Project cache data (~/.claude/projects/ moved, still reproduces)
• Extended attributes (xattr identical to ~/Downloads)
• iCloud sync (not enabled for Documents)
• Filesystem metadata (stat, mdls identical to Downloads)
• Case sensitivity (APFS case-insensitive, same result with ~/documents)

Conclusion

The issue is specific to ~/Documents as the working directory itself — not its contents, not its metadata, not the terminal. Something in v2.1.110's header rendering logic treats this path differently.

Environment

• Version: 2.1.110 (works in 2.1.109)
• OS: macOS (Darwin 25.4.0)
• Terminal: Terminal.app
• Filesystem: APFS (case-insensitive)
• Locale: ko_KR.UTF-8
• Shell: zsh