feat: Add password confirmation for worker scaling + RBAC

- Add /api/auth/verify-password endpoint for re-authentication
- Add PasswordConfirmModal component for sensitive actions
- Worker scaling (+/-) now requires password confirmation
- Add RBAC (ServiceAccount, Role, RoleBinding) for scraper pod
- Scraper pod can now read/scale worker deployment via k8s API

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

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

backend/src/routes/auth.ts

@@ -47,4 +47,27 @@ router.post('/refresh', authMiddleware, async (req: AuthRequest, res) => {
   res.json({ token });
 });
 
+// Verify password for sensitive actions (requires current user to be authenticated)
+router.post('/verify-password', authMiddleware, async (req: AuthRequest, res) => {
+  try {
+    const { password } = req.body;
+
+    if (!password) {
+      return res.status(400).json({ error: 'Password required' });
+    }
+
+    // Re-authenticate the current user with the provided password
+    const user = await authenticateUser(req.user!.email, password);
+
+    if (!user) {
+      return res.status(401).json({ error: 'Invalid password', verified: false });
+    }
+
+    res.json({ verified: true });
+  } catch (error) {
+    console.error('Password verification error:', error);
+    res.status(500).json({ error: 'Internal server error' });
+  }
+});
+
 export default router;