feat: add BlogBodySanitizer for HTML sanitization on article save

- Implemented BlogBodySanitizer to clean HTML content before saving articles, ensuring security against XSS attacks.
- Added tests for BlogBodySanitizer to verify that unsafe tags and attributes are stripped from the content.
- Introduced ApiLeastPrivilegeTest to ensure that unauthorized users cannot access sensitive API routes, maintaining strict access control.

assets/admin/pages/StaffSessionDetailPage.test.tsx

@@ -7,8 +7,8 @@ vi.mock('../lib/api', () => ({
   ApiError: class extends Error {},
 }));
 
-vi.mock('react-router-dom', async () => {
-  const actual = await vi.importActual<typeof import('react-router-dom')>('react-router-dom');
+vi.mock('react-router', async () => {
+  const actual = await vi.importActual<typeof import('react-router')>('react-router');
   return { ...actual, useParams: () => ({ uuid: 'ses-1' }) };
 });