Plan native macOS menus

PLAN.md

@@ -342,6 +342,44 @@ visual placeholders with no message or agent runtime behind them.
 6. Port context compaction and system-prompt reinjection after ordinary
    multi-turn operation is correct.
 
+### Native macOS menus (required with chat)
+
+The application must install and maintain a complete native macOS menu bar;
+the application-name menu alone is not sufficient. Use platform menu roles,
+ordering, selectors, and standard key equivalents rather than drawing menus
+inside the Iced window.
+
+- Provide the standard **Application**, **File**, **Edit**, **View**,
+  **Window**, and **Help** menus. Include the normal macOS Application actions
+  (About, Settings, Services, Hide, Hide Others, Show All, and Quit) and Window
+  actions (Minimize, Zoom, Bring All to Front) with native behavior.
+- Make File actions operate on real application concepts: New Session, Add/Open
+  Project, and Close Window. Make View actions cover actual available views,
+  including sidebar visibility and Enter Full Screen. Help opens the local help
+  or documentation surface. Do not add permanently inert placeholder items.
+- The Edit menu is part of the chat acceptance criteria. Undo, Redo, Cut, Copy,
+  Paste, Paste and Match Style where supported, Delete, and Select All must act
+  on the current first responder. They must work in the chat composer and every
+  other editable text field; Copy and Select All must also work for selectable
+  transcript text.
+- Prefer native first-responder selectors for native controls. Where an Iced
+  widget owns focus, bridge the same menu command into that focused widget so
+  menu clicks and `Command-Z`, `Shift-Command-Z`, `Command-X`, `Command-C`,
+  `Command-V`, and `Command-A` behave identically.
+- Validate menu enabled state whenever focus or application state changes:
+  editing commands reflect the focused selection/clipboard and session/project
+  commands reflect whether their action is currently possible. Menu actions
+  must use the same application messages as toolbar/sidebar actions instead of
+  duplicating business logic.
+- Preserve conventional macOS labels, grouping, keyboard shortcuts, and
+  accessibility metadata. Keep platform-specific menu integration behind the
+  macOS application shell so the chat and session core remain platform-neutral.
+
+Exit criterion: with the composer focused, every standard Edit command works
+from both the menu and its keyboard shortcut, including undo/redo across
+multiple edits; transcript text can be copied; and Application, File, View,
+Window, and Help expose functional, correctly enabled native actions.
+
 ### Dev Brain — Obsidian knowledge and memory
 
 - Add an optional Dev Brain setting in Preferences. Use the native macOS folder