chore(copilot): refresh welcome modal tagline + per-locale font sizing

Tagline copy → "Edit, fill and understand PDFs by chatting with them"
with the chat-based interaction phrase highlighted via the existing
`<accent>` Trans component (rendered as a blue span).

23 locales updated (translator-agent pass). Each translation places
the `<accent>` markers around the natural chat-action phrase in the
target language. ja.json absent from the locales directory; falls
back to the i18next default per existing config.

Per-locale font sizing: en/vi/zh stay at 42px; longer-form locales
(romance, slavic, nordic, fi, tr, hi, ar, he) drop from 42px → 38px
so the line count stays comparable. The `COMPACT_TAGLINE_LOCALES`
heuristic that previously split 48px/42px is reused with the new
sizes.

Author: bendersej

copilot/src/components/demo/welcome_modal.tsx

@@ -13,11 +13,11 @@ const TITLE_ID = 'welcome-modal-title'
 const ILLUSTRATION_URL = 'https://cdn.simplepdf.com/simple-pdf/assets/common/form-copilot-illustration.png'
 const LOGO_URL = 'https://cdn.simplepdf.com/simple-pdf/assets/common/logo-white.png'
 
-// Locales whose `welcomeModal.tagline` translation is short enough to fit
-// in the right pane at the default 48px font size. Everything else
-// (long-tail romance / slavic / nordic / fi / tr / hi / ar / he) renders
-// at 42px so the line count stays roughly the same as EN. CSS `:lang()`
-// could do this without JS, but the locale list reads cleanly as code.
+// Locales whose `welcomeModal.tagline` translation fits at 42px in the
+// right pane. Everything else (longer-form romance / slavic / nordic /
+// fi / tr / hi / ar / he) renders at 38px so the line count stays
+// roughly comparable. CSS `:lang()` could do this without JS, but the
+// locale list reads cleanly as code.
 const COMPACT_TAGLINE_LOCALES = ['en', 'vi', 'zh'] as const
 
 // First-load splash. Rendered inline (NOT through createPortal) so the
@@ -32,7 +32,7 @@ export const WelcomeModal = ({ open, onClose, onOpenInfo }: WelcomeModalProps):
   const { t, i18n } = useTranslation()
   const activeLocale = i18n.language.toLowerCase()
   const isCompactLocale = COMPACT_TAGLINE_LOCALES.some((locale) => activeLocale.startsWith(locale))
-  const taglineFontClass = isCompactLocale ? 'text-[48px]' : 'text-[42px]'
+  const taglineFontClass = isCompactLocale ? 'text-[42px]' : 'text-[38px]'
 
   useEffect(() => {
     if (!open) {

copilot/src/locales/ar.json

@@ -168,7 +168,7 @@
   },
   "welcomeModal": {
     "title": "مرحبًا بك في SimplePDF Copilot",
-    "tagline": "<accent>ذكاء اصطناعي يساعد</accent> المستخدمين على تعبئة نماذج PDF خطوة بخطوة",
+    "tagline": "حرّر ملفات PDF واملأها وافهمها <accent>عبر الدردشة معها</accent>",
     "getStarted": "ابدأ الآن",
     "howItWorks": "كيف يعمل SimplePDF Copilot",
     "close": "إغلاق الترحيب"

copilot/src/locales/cs.json

@@ -162,7 +162,7 @@
   },
   "welcomeModal": {
     "title": "Vítejte ve SimplePDF Copilot",
-    "tagline": "<accent>AI, která pomáhá</accent> uživatelům vyplnit PDF formuláře krok za krokem",
+    "tagline": "Upravujte, vyplňujte a chápejte PDF <accent>pomocí konverzace s nimi</accent>",
     "getStarted": "Začít",
     "howItWorks": "Jak SimplePDF Copilot funguje",
     "close": "Zavřít uvítání"

copilot/src/locales/da.json

@@ -160,7 +160,7 @@
   },
   "welcomeModal": {
     "title": "Velkommen til SimplePDF Copilot",
-    "tagline": "<accent>AI, der hjælper</accent> brugere med at udfylde PDF-formularer trin for trin",
+    "tagline": "Rediger, udfyld og forstå PDF-filer <accent>ved at chatte med dem</accent>",
     "getStarted": "Kom i gang",
     "howItWorks": "Sådan fungerer SimplePDF Copilot",
     "close": "Luk velkomst"

copilot/src/locales/de.json

@@ -160,7 +160,7 @@
   },
   "welcomeModal": {
     "title": "Willkommen bei SimplePDF Copilot",
-    "tagline": "<accent>KI, die hilft</accent>, PDF-Formulare Schritt für Schritt auszufüllen",
+    "tagline": "PDFs bearbeiten, ausfüllen und verstehen, <accent>indem Sie mit ihnen chatten</accent>",
     "getStarted": "Loslegen",
     "howItWorks": "So funktioniert SimplePDF Copilot",
     "close": "Begrüßung schließen"

copilot/src/locales/el.json

@@ -160,7 +160,7 @@
   },
   "welcomeModal": {
     "title": "Καλώς ήρθατε στο SimplePDF Copilot",
-    "tagline": "<accent>AI που βοηθά</accent> τους χρήστες να συμπληρώνουν φόρμες PDF βήμα βήμα",
+    "tagline": "Επεξεργαστείτε, συμπληρώστε και κατανοήστε PDF <accent>συνομιλώντας μαζί τους</accent>",
     "getStarted": "Ξεκινήστε",
     "howItWorks": "Πώς λειτουργεί το SimplePDF Copilot",
     "close": "Κλείσιμο καλωσορίσματος"

copilot/src/locales/en.json

@@ -178,7 +178,7 @@
   },
   "welcomeModal": {
     "title": "Welcome to SimplePDF Copilot",
-    "tagline": "<accent>AI that helps</accent> users fill PDF forms step by step",
+    "tagline": "Edit, fill and understand PDFs <accent>by chatting with them</accent>",
     "getStarted": "Get started",
     "howItWorks": "How SimplePDF Copilot works",
     "close": "Close welcome"

copilot/src/locales/es.json

@@ -160,7 +160,7 @@
   },
   "welcomeModal": {
     "title": "Te damos la bienvenida a SimplePDF Copilot",
-    "tagline": "<accent>IA que ayuda</accent> a los usuarios a completar formularios PDF paso a paso",
+    "tagline": "Edita, rellena y entiende los PDF <accent>chateando con ellos</accent>",
     "getStarted": "Empezar",
     "howItWorks": "Cómo funciona SimplePDF Copilot",
     "close": "Cerrar bienvenida"

copilot/src/locales/et.json

@@ -160,7 +160,7 @@
   },
   "welcomeModal": {
     "title": "Tere tulemast SimplePDF Copilotisse",
-    "tagline": "<accent>Tehisintellekt, mis aitab</accent> kasutajatel samm-sammult PDF-vorme täita",
+    "tagline": "Muutke, täitke ja mõistke PDF-e <accent>nendega vesteldes</accent>",
     "getStarted": "Alusta",
     "howItWorks": "Kuidas SimplePDF Copilot töötab",
     "close": "Sulge tervitus"

copilot/src/locales/fi.json

@@ -160,7 +160,7 @@
   },
   "welcomeModal": {
     "title": "Tervetuloa SimplePDF Copilotiin",
-    "tagline": "<accent>Tekoäly, joka auttaa</accent> käyttäjiä täyttämään PDF-lomakkeita vaihe vaiheelta",
+    "tagline": "Muokkaa, täytä ja ymmärrä PDF-tiedostoja <accent>keskustelemalla niiden kanssa</accent>",
     "getStarted": "Aloita",
     "howItWorks": "Näin SimplePDF Copilot toimii",
     "close": "Sulje tervetulo"