feat(ui): add session history navigation, permission keys, and review shortcuts

mod+alt+arrows step through this window's session-open history (or between
neighbouring tabs when session tabs are on), mod+k r renames the current
session inline, and mod+k a toggles permission auto-accept. Pending
permission cards respond to alt+enter / alt+shift+enter / alt+backspace with
the keys printed on the buttons. The commit message box commits on
mod+enter, alt+arrows step the diff review between changed files, and the
command palette gains search-only commands for rare actions so the initial
list stays short.

packages/ui/src/components/layout/Header.tsx

@@ -1463,6 +1463,10 @@ export const Header: React.FC = () => {
 
 
   useKeybinds({
+    rename_current_session: () => {
+      if (!currentSessionId || isMobile) return false;
+      beginHeaderSessionRename();
+    },
     toggle_services_menu: () => {
       if (isDesktopServicesOpen) {
         setIsDesktopServicesOpen(false);