feat!: rewrite frontend in Vue 3 with Pinia, DaisyUI, vite-plugin-pwa

Migrates every component from class-based vue-property-decorator to
<script setup> + Composition API. Replaces Vuex 3 + vuex-class with a
single Pinia store (persisted via pinia-plugin-persistedstate). Swaps
Bulma + bulma-{checkradio,switch,pricingtable} for DaisyUI 5 utilities
on Tailwind 4. Replaces register-service-worker with vite-plugin-pwa
(workbox, skipWaiting/clientsClaim preserved).

Plugins replaced:
- vue-class-component / vue-property-decorator -> <script setup>
- vuex / vuex-class / vuex-persist -> pinia + persistedstate
- vue-i18n 8 -> vue-i18n 11 (composition mode, legacy: false)
- vue-click-outside -> @vueuse/core onClickOutside
- @xkeshi/vue-qrcode -> qrcode.vue
- vue-currency-input 1 -> vue-currency-input 3 (composable wrapper)
- bus-event (Vue instance) -> mitt
- Vue filters -> plain functions imported per component

BREAKING: drops Stripe / pricing entirely (Payment, PricingTable,
/pricing route, vue-stripe-checkout, bulma-pricingtable).

Clears unused Cypress and Jest test scaffolding; leaves a Vitest
harness behind for future tests.

src/utils/format.ts

@@ -0,0 +1,41 @@
+import type ICurrency from '@/models/ICurrency'
+
+export const money = (
+  value: number,
+  currency: ICurrency | null | undefined,
+  country = 'fr-FR'
+): string => {
+  if (!currency) {
+    return value.toString()
+  }
+  return new Intl.NumberFormat(country, {
+    style: 'currency',
+    currency: currency.code,
+    minimumFractionDigits: 2
+  }).format(value)
+}
+
+export const moneypad = (
+  value: number,
+  currency?: ICurrency | null,
+  withPadEnd = true
+): string => {
+  const m = money(value, currency)
+  const s: string[] = m.split('\xa0')
+  let cur: string | undefined = s.pop()
+  if (withPadEnd) {
+    cur = (cur || '').padEnd(3, '\xa0')
+  }
+  return `${s.join('\xa0')}\xa0${cur || ''}`
+}
+
+export const date = (value: string, country = 'fr-FR') =>
+  new Intl.DateTimeFormat(country).format(new Date(value))
+
+export const fulldate = (value: string, country = 'fr-FR') =>
+  new Intl.DateTimeFormat(country, {
+    weekday: 'long',
+    year: 'numeric',
+    month: 'long',
+    day: 'numeric'
+  }).format(new Date(value))