feat: remove nuxt i18n for in house i18n for web (#5131)

* feat: remove nuxt i18n for in house

* cleanup: remove old nuxt/i18n patch

* prepr

---------

Co-authored-by: Prospector <6166773+Prospector@users.noreply.github.com>

apps/app-frontend/src/main.js

@@ -8,7 +8,7 @@ import { createPinia } from 'pinia'
 import { createApp } from 'vue'
 
 import App from '@/App.vue'
-import i18n from '@/i18n.config'
+import i18nPlugin from '@/plugins/i18n'
 import router from '@/routes'
 
 const vueScan = new VueScanPlugin({
@@ -43,6 +43,6 @@ app.use(FloatingVue, {
 		},
 	},
 })
-app.use(i18n)
+app.use(i18nPlugin)
 
 app.mount('#app')

apps/app-frontend/src/plugins/i18n.ts

@@ -0,0 +1,23 @@
+import { I18N_INJECTION_KEY, type I18nContext } from '@modrinth/ui'
+import type { App } from 'vue'
+
+import i18n from '@/i18n.config'
+
+export default {
+	install(app: App) {
+		// Install vue-i18n as before
+		app.use(i18n)
+
+		// Wrap it in our I18nContext interface
+		const context: I18nContext = {
+			locale: i18n.global.locale,
+			t: (key, values) => i18n.global.t(key, values ?? {}) as string,
+			setLocale: (newLocale) => {
+				i18n.global.locale.value = newLocale
+			},
+		}
+
+		// Provide the context at app-level
+		app.provide(I18N_INJECTION_KEY, context)
+	},
+}