fix(frontend): Fix lint and type errors in test files

- Remove unused imports (fireEvent, IssueStatus) in issue component tests
- Add E2E global type declarations for __TEST_AUTH_STORE__
- Fix toHaveAccessibleName assertion with regex pattern

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

frontend/tests/features/issues/components/IssueFilters.test.tsx

@@ -2,7 +2,7 @@
  * IssueFilters Component Tests
  */
 
-import { render, screen, fireEvent } from '@testing-library/react';
+import { render, screen } from '@testing-library/react';
 import userEvent from '@testing-library/user-event';
 import { IssueFilters } from '@/features/issues/components/IssueFilters';
 import type { IssueFilters as IssueFiltersType } from '@/features/issues/types';

frontend/tests/features/issues/components/IssueTable.test.tsx

@@ -2,7 +2,7 @@
  * IssueTable Component Tests
  */
 
-import { render, screen, fireEvent } from '@testing-library/react';
+import { render, screen } from '@testing-library/react';
 import userEvent from '@testing-library/user-event';
 import { IssueTable } from '@/features/issues/components/IssueTable';
 import type { IssueSummary, IssueSort } from '@/features/issues/types';

frontend/tests/features/issues/components/StatusWorkflow.test.tsx

@@ -5,7 +5,6 @@
 import { render, screen } from '@testing-library/react';
 import userEvent from '@testing-library/user-event';
 import { StatusWorkflow } from '@/features/issues/components/StatusWorkflow';
-import type { IssueStatus } from '@/features/issues/types';
 
 describe('StatusWorkflow', () => {
   const mockOnStatusChange = jest.fn();