Emoji in U+1F000+ have no stable column-width contract across terminal
emulators. On cmd.exe/PowerShell they render as 1-column placeholder
boxes even though unicode_width reports 2; on WezTerm/Alacritty with
certain font stacks the rendered width can be off by one column. Both
cases break layout arithmetic in the header and file-tree widgets.
Changes:
- header.rs: replace 🐳 (U+1F433, 2-wide) with ◆ (U+25C6, always 1-wide)
in the "max" reasoning-effort chip
- file_tree.rs: drop the 📁/📄 (U+1F4C1/U+1F4C4) entry-icon prefix; the
▼/▶ expand marker already distinguishes dirs from files
Fixes#1314
AutoGHClaw
4bc5375fa6