fix: resolve all lint errors from L4 feature

- Remove unused Box/Collapse from L4PortsApplyBanner
- Remove unused Stack from RedirectsFields
- Remove unused updateL4ProxyHost import from validation test
- Add eslint-disable-next-line for require() in vi.hoisted() blocks
  (necessary pattern since vi.hoisted runs before ESM imports)
- Add file-level eslint-disable no-explicit-any for test files that
  intentionally pass invalid types to test validation logic

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/components/proxy-hosts/RedirectsFields.tsx

@@ -1,7 +1,7 @@
 "use client";
 import { useState } from "react";
 import {
-  Box, Button, IconButton, MenuItem, Select, Stack,
+  Box, Button, IconButton, MenuItem, Select,
   Table, TableBody, TableCell, TableHead, TableRow, TextField, Typography,
 } from "@mui/material";
 import DeleteIcon from "@mui/icons-material/Delete";