chore: upgrade npm deps — vite 8, prettier plugins, @types/node, @eslint/compat

Upgrades applied:
  @types/node: 22.20.1 → 26.1.1
  @eslint/compat: 1.4.1 → 2.1.0
  prettier-plugin-tailwindcss: 0.7.4 → 0.8.0
  prettier-plugin-svelte: 3.5.2 → 4.1.1 (formatted textarea.svelte)
  vite: 7.3.6 → 8.1.4
  @sveltejs/vite-plugin-svelte: 6.2.4 → 7.2.0

Left at current (blocked by deps chain):
  eslint / @eslint/js — typescript-eslint needs eslint 10 support
  typescript — typescript-eslint needs TS 7 support

Added CI TODO note for when vite-plugin-svelte-inspector catches up.

frontend/src/lib/components/ui/textarea/textarea.svelte

@@ -19,5 +19,4 @@
 		className
 	)}
 	bind:value
-	{...restProps}
-></textarea>
+	{...restProps}></textarea>

frontend/src/routes/account/+page.svelte

@@ -11,12 +11,12 @@
 	import { savedCardsStore, type SavedCard } from '$lib/stores/savedCards.svelte';
 
 	// zxcvbn-ts imports
-	import { zxcvbn, zxcvbnOptions } from '@zxcvbn-ts/core';
+	import { ZxcvbnFactory } from '@zxcvbn-ts/core';
 	import * as languageCommon from '@zxcvbn-ts/language-common';
 	import * as languageEn from '@zxcvbn-ts/language-en';
 
 	// set up options so that feedback, dictionary etc. are included
-	zxcvbnOptions.setOptions({
+	const zxcvbn = new ZxcvbnFactory({
 		translations: languageEn.translations,
 		graphs: languageCommon.adjacencyGraphs,
 		dictionary: {
@@ -1111,7 +1111,7 @@
 	let changingPassword = $state(false);
 
 	// Password strength using zxcvbn
-	const newPasswordStrength = $derived(passwordData.new ? zxcvbn(passwordData.new) : null);
+	const newPasswordStrength = $derived(passwordData.new ? zxcvbn.check(passwordData.new) : null);
 	const isPasswordStrongEnough = $derived(
 		!passwordData.new || newPasswordStrength === null || newPasswordStrength.score >= 2
 	);

frontend/src/routes/login/+page.svelte

@@ -11,14 +11,14 @@
 	import { SvelteDate } from 'svelte/reactivity';
 
 	// zxcvbn-ts imports
-	import { zxcvbn, zxcvbnOptions } from '@zxcvbn-ts/core';
+	import { ZxcvbnFactory } from '@zxcvbn-ts/core';
 	import * as languageCommon from '@zxcvbn-ts/language-common';
 	import * as languageEn from '@zxcvbn-ts/language-en';
 	import { toast } from 'svelte-sonner';
 	import { sanitizeText } from '$lib/utils/toast-safe';
 
 	// set up options so that feedback, dictionary etc. are included
-	zxcvbnOptions.setOptions({
+	const zxcvbn = new ZxcvbnFactory({
 		translations: languageEn.translations,
 		graphs: languageCommon.adjacencyGraphs,
 		dictionary: {
@@ -229,7 +229,7 @@
 	const passwordStrength = $derived(
 		formData.password
 			? (() => {
-					const result = zxcvbn(formData.password);
+					const result = zxcvbn.check(formData.password);
 					// Add minimum length check (6 chars) to the score feedback
 					if (formData.password.length < 6) {
 						return {