Problem

The native macOS chat window is a single fixed column hosted in a bare NSWindow: session, thinking, and model pickers are crammed into a small strip above the composer, sessions are only reachable through a cramped dropdown of raw routing keys (agent:main:main), and the transcript sits on a dated orange/teal gradient. Compared to the web Control UI the native surface is missing core functionality:

• no sessions sidebar (list, search, pin, delete, new session)
• /new silently falls back to sessions.reset because the Mac transport never implemented sessions.create
• no slash-command autocomplete (the shared panel is iOS-only; the Mac transport does not implement commands.list)
• no context-window/token/cost visibility
• no message copy actions, no transcript export surfaced, no compact/clear-history affordances

Proposal

Redesign the macOS chat window as a proper native shell while keeping the compact menu-bar panel:

• NavigationSplitView shell in OpenClawChatUI (macOS-only): searchable sessions sidebar (pinned/recent sections, unread dots, pin/delete context menus, connection footer) plus a unified toolbar carrying model picker, thinking picker, context-usage ring (tokens/cost, compact action), and a session actions menu (new ⌘N, refresh ⌘R, copy key, export transcript ⇧⌘E, compact, clear history)
• clean iMessage-style composer chrome; assistant messages render as plain flowing text, user messages in accent bubbles following the system accent color
• slash-command autocomplete on macOS with full keyboard navigation (↑/↓/Tab/Return/Esc)
• Mac gateway transport implements commands.list, sessions.create, sessions.patch, sessions.delete
• message context menu (Copy Message), refreshed empty state, native window chrome with frame persistence

Full web-UI parity (split panes, checkpoints, workspace rail, talk mode in window, thread search) stays follow-up work; this covers the structural redesign plus the highest-value parity gaps.