7b037f0efa
MiniMax Code CLI 0.3.1 added a status-line segment showing the git branch for the current workspace. Hermes' status bar had no repo-awareness field. Adds `git_branch` to display.status_bar.fields (opt-in only — the default set never probes the filesystem). Reads .git/HEAD directly with a 5s per-directory TTL cache (no subprocess per repaint); follows gitdir: pointer files so worktrees/submodules resolve their private HEAD; a detached HEAD renders the abbreviated commit. Inspired by MiniMax Code CLI 0.3.1 changelog (agent.minimax.io/docs/changelog).