Fix: localize reply/forward quote header incl. sender address

The reply/forward quote header was always emitted in English ("On {date},
{from} wrote:", "---------- Forwarded message ----------", From/Date/Subject)
regardless of UI language, in both the main path (lib/quote-header.ts) and the
composer's inline fallback. quote-header.ts now takes an optional localized
QuoteHeaderLabels set (English defaults preserved for back-compat); page.tsx
builds it from a new quote_header message namespace, and the composer fallback
uses the same keys. Added the quote_header namespace to all 17 locales.

Also folds in the forward-sender-address fix: the forward "From:" line now
shows the full "Name <email>" like every mail client (the reply line keeps the
bare name, which reads naturally in "On … wrote:").

locales/cs/common.json

@@ -1,4 +1,11 @@
 {
+  "quote_header": {
+    "reply_line": "Dne {date} napsal(a) {from}:",
+    "forwarded_separator": "---------- Přeposlaná zpráva ----------",
+    "from_label": "Od",
+    "date_label": "Datum",
+    "subject_label": "Předmět"
+  },
   "login": {
     "title": "Webmail",
     "username_label": "E-mail",

locales/da/common.json

@@ -1,4 +1,11 @@
 {
+  "quote_header": {
+    "reply_line": "Den {date} skrev {from}:",
+    "forwarded_separator": "---------- Videresendt besked ----------",
+    "from_label": "Fra",
+    "date_label": "Dato",
+    "subject_label": "Emne"
+  },
   "login": {
     "title": "Webmail",
     "username_label": "Email",

locales/de/common.json

@@ -1,4 +1,11 @@
 {
+  "quote_header": {
+    "reply_line": "Am {date} schrieb {from}:",
+    "forwarded_separator": "---------- Weitergeleitete Nachricht ----------",
+    "from_label": "Von",
+    "date_label": "Datum",
+    "subject_label": "Betreff"
+  },
   "login": {
     "title": "Webmail",
     "username_label": "E-Mail",

locales/en/common.json

@@ -1,4 +1,11 @@
 {
+  "quote_header": {
+    "reply_line": "On {date}, {from} wrote:",
+    "forwarded_separator": "---------- Forwarded message ----------",
+    "from_label": "From",
+    "date_label": "Date",
+    "subject_label": "Subject"
+  },
   "login": {
     "title": "Webmail",
     "username_label": "Email",

locales/es/common.json

@@ -1,4 +1,11 @@
 {
+  "quote_header": {
+    "reply_line": "El {date}, {from} escribió:",
+    "forwarded_separator": "---------- Mensaje reenviado ----------",
+    "from_label": "De",
+    "date_label": "Fecha",
+    "subject_label": "Asunto"
+  },
   "login": {
     "title": "Correo Web",
     "username_label": "Correo electrónico",

locales/fr/common.json

@@ -1,4 +1,11 @@
 {
+  "quote_header": {
+    "reply_line": "Le {date}, {from} a écrit :",
+    "forwarded_separator": "---------- Message transféré ----------",
+    "from_label": "De",
+    "date_label": "Date",
+    "subject_label": "Sujet"
+  },
   "login": {
     "title": "Webmail",
     "username_label": "Email",

locales/it/common.json

@@ -1,4 +1,11 @@
 {
+  "quote_header": {
+    "reply_line": "Il {date}, {from} ha scritto:",
+    "forwarded_separator": "---------- Messaggio inoltrato ----------",
+    "from_label": "Da",
+    "date_label": "Data",
+    "subject_label": "Oggetto"
+  },
   "login": {
     "title": "Webmail",
     "username_label": "Email",

locales/ja/common.json

@@ -1,4 +1,11 @@
 {
+  "quote_header": {
+    "reply_line": "{date}に{from}が書きました:",
+    "forwarded_separator": "---------- 転送メッセージ ----------",
+    "from_label": "差出人",
+    "date_label": "日付",
+    "subject_label": "件名"
+  },
   "login": {
     "title": "ウェブメール",
     "username_label": "メールアドレス",

locales/ko/common.json

@@ -1,4 +1,11 @@
 {
+  "quote_header": {
+    "reply_line": "{date}에 {from}님이 작성:",
+    "forwarded_separator": "---------- 전달된 메시지 ----------",
+    "from_label": "보낸 사람",
+    "date_label": "날짜",
+    "subject_label": "제목"
+  },
   "login": {
     "title": "웹메일",
     "username_label": "이메일",

locales/lv/common.json

@@ -1,4 +1,11 @@
 {
+  "quote_header": {
+    "reply_line": "{date} {from} rakstīja:",
+    "forwarded_separator": "---------- Pārsūtītā ziņa ----------",
+    "from_label": "No",
+    "date_label": "Datums",
+    "subject_label": "Tēma"
+  },
   "login": {
     "title": "Tīmekļa pasts",
     "username_label": "E-pasta adrese",

locales/nl/common.json

@@ -1,4 +1,11 @@
 {
+  "quote_header": {
+    "reply_line": "Op {date} schreef {from}:",
+    "forwarded_separator": "---------- Doorgestuurd bericht ----------",
+    "from_label": "Van",
+    "date_label": "Datum",
+    "subject_label": "Onderwerp"
+  },
   "login": {
     "title": "Webmail",
     "username_label": "E-mail",

locales/pl/common.json

@@ -1,4 +1,11 @@
 {
+  "quote_header": {
+    "reply_line": "{date}, {from} napisał(a):",
+    "forwarded_separator": "---------- Wiadomość przekazana ----------",
+    "from_label": "Od",
+    "date_label": "Data",
+    "subject_label": "Temat"
+  },
   "login": {
     "title": "Webmail",
     "username_label": "E-mail",

locales/pt/common.json

@@ -1,4 +1,11 @@
 {
+  "quote_header": {
+    "reply_line": "Em {date}, {from} escreveu:",
+    "forwarded_separator": "---------- Mensagem encaminhada ----------",
+    "from_label": "De",
+    "date_label": "Data",
+    "subject_label": "Assunto"
+  },
   "login": {
     "title": "Webmail",
     "username_label": "E-mail",

locales/ru/common.json

@@ -1,4 +1,11 @@
 {
+  "quote_header": {
+    "reply_line": "{date}, {from} написал:",
+    "forwarded_separator": "---------- Пересланное сообщение ----------",
+    "from_label": "От",
+    "date_label": "Дата",
+    "subject_label": "Тема"
+  },
   "login": {
     "title": "Веб-почта",
     "username_label": "Электронная почта",

locales/tr/common.json

@@ -1,4 +1,11 @@
 {
+  "quote_header": {
+    "reply_line": "{date} tarihinde {from} şunu yazdı:",
+    "forwarded_separator": "---------- İletilen mesaj ----------",
+    "from_label": "Kimden",
+    "date_label": "Tarih",
+    "subject_label": "Konu"
+  },
   "login": {
     "title": "Webmail",
     "username_label": "E-posta",

locales/uk/common.json

@@ -1,4 +1,11 @@
 {
+  "quote_header": {
+    "reply_line": "{date}, {from} написав:",
+    "forwarded_separator": "---------- Переслане повідомлення ----------",
+    "from_label": "Від",
+    "date_label": "Дата",
+    "subject_label": "Тема"
+  },
   "login": {
     "title": "Веб-пошта",
     "username_label": "Електронна пошта",

locales/zh/common.json

@@ -1,4 +1,11 @@
 {
+  "quote_header": {
+    "reply_line": "在 {date}，{from} 写道：",
+    "forwarded_separator": "---------- 转发邮件 ----------",
+    "from_label": "发件人",
+    "date_label": "日期",
+    "subject_label": "主题"
+  },
   "login": {
     "title": "网页邮箱",
     "username_label": "邮箱地址",