test: migrate browser_tests/ to @e2e/ path alias and add lint rule (#10958)

## Summary

Complete the @e2e/ path alias migration started in #10735 by converting
all 354 remaining relative imports and adding a lint rule to prevent
backsliding.

## Changes

- **What**: Migrate all relative imports in browser_tests/ to use
`@e2e/` (intra-directory) and `@/` (src/ imports) path aliases. Add
`no-restricted-imports` ESLint rule banning `./` and `../` imports in
`browser_tests/**/*.ts`. Suppress pre-existing oxlint `no-eval` and
`no-console` warnings exposed by touching those files.

## Review Focus

- ESLint flat-config merging: the `@playwright/test` ban and
relative-import ban are in two separate blocks to avoid last-match-wins
collision with the `useI18n`/`useVirtualList` blocks higher in the
config.
- The `['./**', '../**']` glob patterns (not `['./*', '../*']`) are
needed to catch multi-level relative paths like `../../../src/foo`.

Follows up on #10735

┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-10958-test-migrate-browser_tests-to-e2e-path-alias-and-add-lint-rule-33c6d73d365081649d1be771eac986fd)
by [Unito](https://www.unito.io)

Co-authored-by: Amp <amp@ampcode.com>

browser_tests/tests/vueNodes/widgets/text/multilineStringWidget.spec.ts

@@ -1,8 +1,8 @@
 import {
   comfyExpect as expect,
   comfyPageFixture as test
-} from '../../../../fixtures/ComfyPage'
-import type { ComfyPage } from '../../../../fixtures/ComfyPage'
+} from '@e2e/fixtures/ComfyPage'
+import type { ComfyPage } from '@e2e/fixtures/ComfyPage'
 
 test.describe('Vue Multiline String Widget', () => {
   test.beforeEach(async ({ comfyPage }) => {