fix(frontend): show confirmation notice when registration requires email verification

After a successful registration the frontend auto-logs-in. With email
confirmation enabled that login fails with 412 (code 1012), which
surfaced as a raw "Request failed with status code 412" error in the
register form even though the account was created fine. Treat that case
as a success and tell the user to check their inbox instead.

frontend/src/i18n/lang/en.json

@@ -104,7 +104,8 @@
       "remember": "Stay logged in",
       "registrationDisabled": "Registration is disabled.",
       "passwordResetTokenMissing": "Password reset token is missing.",
-      "registrationFailed": "An error occurred during registration. Please check your input and try again."
+      "registrationFailed": "An error occurred during registration. Please check your input and try again.",
+      "registrationConfirmEmail": "Your account was created successfully! Please check your inbox and click the link in the confirmation email before logging in."
     },
     "settings": {
       "bots": {

frontend/src/stores/auth.ts

@@ -238,12 +238,12 @@ export const useAuthStore = defineStore('auth', () => {
 				...credentials,
 				language,
 			})
-			return login(credentials)
+			return await login(credentials)
 		} catch (e) {
 			if (e.response?.data?.code === 2002 && e.response?.data?.invalid_fields[0]?.startsWith('language:')) {
 				return register(credentials, 'en')
 			}
-			
+
 			if (e.response?.data?.message) {
 				throw e.response.data
 			}

frontend/src/views/user/Register.vue

@@ -7,6 +7,13 @@
 		>
 			{{ errorMessage }}
 		</Message>
+		<Message
+			v-if="confirmEmailMessage !== ''"
+			variant="success"
+			class="mbe-4"
+		>
+			{{ confirmEmailMessage }}
+		</Message>
 		<form
 			id="registerform"
 			@submit.prevent="submit"
@@ -136,6 +143,7 @@ const credentials = reactive({
 
 const isLoading = computed(() => authStore.isLoading)
 const errorMessage = ref('')
+const confirmEmailMessage = ref('')
 const validatePasswordInitially = ref(false)
 const serverValidationErrors = ref<Partial<Record<string, string>>>({})
 
@@ -233,6 +241,12 @@ async function submit() {
 		await authStore.register(toRaw(credentials))
 		redirectIfSaved()
 	} catch (e: unknown) {
+		// 1012 = email not confirmed: registration itself succeeded
+		if (e instanceof Object && 'code' in e && e.code === 1012) {
+			confirmEmailMessage.value = t('user.auth.registrationConfirmEmail')
+			return
+		}
+
 		// Parse field-specific validation errors
 		if (isApiValidationError(e)) {
 			const fieldErrors = parseValidationErrors(e)