fix: resolve i18n no-restricted-imports lint warnings (#8704)

## Summary

Fix all i18n `no-restricted-imports` lint warnings and upgrade rules
from `warn` to `error`.

## Changes

- **What**: Migrate Vue components from `import { t/d } from '@/i18n'`
to `const { t } = useI18n()`. Migrate non-component `.ts` files from
`useI18n()` to `import { t/d } from '@/i18n'`. Allow `st` import from
`@/i18n` in Vue components (it wraps `te`/`t` for safe fallback
translation). Remove `@deprecated` tag from `i18n.ts` global exports
(still used by `st` and non-component code). Upgrade both lint rules
from `warn` to `error`.

## Review Focus

- The `st` helper is intentionally excluded from the Vue component
restriction since it provides safe fallback translation needed for
custom node definitions.

Fixes #8701

┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-8704-fix-resolve-i18n-no-restricted-imports-lint-warnings-2ff6d73d365081ae84d8eb0dfef24323)
by [Unito](https://www.unito.io)

---------

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

src/components/load3d/controls/viewer/ViewerCameraControls.vue

@@ -30,10 +30,11 @@
 import Select from 'primevue/select'
 import Slider from 'primevue/slider'
 import { computed } from 'vue'
+import { useI18n } from 'vue-i18n'
 
 import type { CameraType } from '@/extensions/core/load3d/interfaces'
-import { t } from '@/i18n'
 
+const { t } = useI18n()
 const cameras = [
   { title: t('load3d.cameraType.perspective'), value: 'perspective' },
   { title: t('load3d.cameraType.orthographic'), value: 'orthographic' }