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/views/DiffView.tsx

@@ -1768,6 +1768,37 @@ export const DiffView: React.FC<DiffViewProps> = ({
         scrollToFile(value);
     }, [cancelPendingScrollAlignment, expandStackedFile, scrollToFile]);
 
+    // Step review to the adjacent changed file (alt+arrow): selects, expands
+    // a collapsed section, and scrolls to it. Window-level because the diff
+    // surface has no persistent focus target; guarded off editable fields.
+    React.useEffect(() => {
+        const handleKeyDown = (event: KeyboardEvent) => {
+            if (!event.altKey || event.metaKey || event.ctrlKey || event.shiftKey) return;
+            if (event.key !== 'ArrowDown' && event.key !== 'ArrowUp') return;
+            const target = event.target;
+            if (target instanceof HTMLElement && (
+                target.isContentEditable
+                || target.tagName === 'INPUT'
+                || target.tagName === 'TEXTAREA'
+                || target.closest('[role="dialog"]')
+            )) {
+                return;
+            }
+            if (changedFiles.length === 0) return;
+            const delta = event.key === 'ArrowDown' ? 1 : -1;
+            const index = displayFile ? changedFiles.findIndex((file) => file.path === displayFile) : -1;
+            const nextIndex = index === -1
+                ? (delta > 0 ? 0 : changedFiles.length - 1)
+                : index + delta;
+            const next = changedFiles[nextIndex];
+            if (!next) return;
+            event.preventDefault();
+            handleSelectFileAndScroll(next.path);
+        };
+        window.addEventListener('keydown', handleKeyDown);
+        return () => window.removeEventListener('keydown', handleKeyDown);
+    }, [changedFiles, displayFile, handleSelectFileAndScroll]);
+
     const handleHeaderLayoutChange = React.useCallback((mode: DiffViewMode) => {
         const nextLayout: 'inline' | 'side-by-side' =
             mode === 'side-by-side' ? 'side-by-side' : 'inline';

packages/ui/src/components/views/git/CommitInput.tsx

@@ -6,6 +6,7 @@ import { useI18n } from '@/lib/i18n';
 interface CommitInputProps {
   value: string;
   onChange: (value: string) => void;
+  onSubmit?: () => void;
   placeholder?: string;
   disabled?: boolean;
   hasTouchInput?: boolean;
@@ -18,6 +19,7 @@ const MAX_HEIGHT = 200;
 export const CommitInput: React.FC<CommitInputProps> = ({
   value,
   onChange,
+  onSubmit,
   placeholder,
   disabled = false,
   hasTouchInput = false,
@@ -58,6 +60,12 @@ export const CommitInput: React.FC<CommitInputProps> = ({
       ref={textareaRef}
       value={value}
       onChange={(e) => onChange(e.target.value)}
+      onKeyDown={(e) => {
+        if (e.key === 'Enter' && (e.metaKey || e.ctrlKey) && !e.shiftKey && !e.altKey) {
+          e.preventDefault();
+          onSubmit?.();
+        }
+      }}
       placeholder={placeholder ?? t('gitView.commit.messagePlaceholder')}
       rows={1}
       disabled={disabled}

packages/ui/src/components/views/git/CommitSection.tsx

@@ -68,6 +68,9 @@ export const CommitSection: React.FC<CommitSectionProps> = ({
         <CommitInput
           value={commitMessage}
           onChange={onCommitMessageChange}
+          onSubmit={() => {
+            if (canCommit && !isGeneratingMessage) onCommit();
+          }}
           placeholder={t('gitView.commit.messagePlaceholder')}
           disabled={commitAction !== null}
           hasTouchInput={hasTouchInput}