refactor: migrate checks.ts utility to core and deduplicate (#18139)

packages/cli/src/ui/components/AskUserDialog.tsx

@@ -21,7 +21,7 @@ import type { SelectionListItem } from '../hooks/useSelectionList.js';
 import { TabHeader, type Tab } from './shared/TabHeader.js';
 import { useKeypress, type Key } from '../hooks/useKeypress.js';
 import { keyMatchers, Command } from '../keyMatchers.js';
-import { checkExhaustive } from '../../utils/checks.js';
+import { checkExhaustive } from '@google/gemini-cli-core';
 import { TextInput } from './shared/TextInput.js';
 import { useTextBuffer } from './shared/text-buffer.js';
 import { getCachedStringWidth } from '../utils/textUtils.js';

packages/cli/src/ui/components/ChecklistItem.tsx

@@ -7,7 +7,7 @@
 import type React from 'react';
 import { Box, Text } from 'ink';
 import { theme } from '../semantic-colors.js';
-import { checkExhaustive } from '../../utils/checks.js';
+import { checkExhaustive } from '@google/gemini-cli-core';
 
 export type ChecklistStatus =
   | 'pending'

packages/cli/src/ui/components/shared/vim-buffer-actions.ts

@@ -19,7 +19,7 @@ import {
   findWordEndInLine,
 } from './text-buffer.js';
 import { cpLen, toCodePoints } from '../../utils/textUtils.js';
-import { assumeExhaustive } from '../../../utils/checks.js';
+import { assumeExhaustive } from '@google/gemini-cli-core';
 
 // Check if we're at the end of a base word (on the last base character)
 // Returns true if current position has a base character followed only by combining marks until non-word