refactor(sidebar): streamline conversation list with completed filter and expand toggle

Replace flat/grouped view toggle with a show-completed filter dropdown,
add expand/collapse-all control, extract status icon component, and
simplify the sidebar header.

src/i18n/messages/ar.json

@@ -834,8 +834,12 @@
       "statsLabel": "{folders} مجلدات · {convos} محادثة",
       "openFolder": "فتح مجلد",
       "searchPlaceholder": "بحث عن محادثات...",
-      "viewFlat": "عرض مسطح",
-      "viewGrouped": "تجميع حسب المجلد",
+      "showCompleted": "عرض المحادثات المكتملة",
+      "moreOptions": "المزيد من الخيارات",
+      "statusRunningBadge": "قيد التشغيل",
+      "statusFailedBadge": "فشل",
+      "conversationCountUnit": "{count} محادثة",
+      "emptyFolderHint": "لا توجد محادثات",
       "noMatchingConversations": "لا توجد محادثات مطابقة",
       "removeFolderConfirmTitle": "إزالة المجلد من مساحة العمل؟",
       "removeFolderConfirmDescription": "إزالة \"{name}\" من مساحة العمل؟ سيتم إغلاق علامات التبويب والمحطات المرتبطة.",

src/i18n/messages/de.json

@@ -834,8 +834,12 @@
       "statsLabel": "{folders} Ordner · {convos} Konversationen",
       "openFolder": "Ordner öffnen",
       "searchPlaceholder": "Konversationen suchen...",
-      "viewFlat": "Flache Ansicht",
-      "viewGrouped": "Nach Ordner gruppieren",
+      "showCompleted": "Abgeschlossene Konversationen anzeigen",
+      "moreOptions": "Weitere Optionen",
+      "statusRunningBadge": "Läuft",
+      "statusFailedBadge": "Fehlgeschlagen",
+      "conversationCountUnit": "{count, plural, one {# Konversation} other {# Konversationen}}",
+      "emptyFolderHint": "Keine Konversationen",
       "noMatchingConversations": "Keine passenden Konversationen",
       "removeFolderConfirmTitle": "Ordner aus Arbeitsbereich entfernen?",
       "removeFolderConfirmDescription": "\"{name}\" aus dem Arbeitsbereich entfernen? Zugehörige Tabs und Terminals werden geschlossen.",

src/i18n/messages/en.json

@@ -834,8 +834,12 @@
       "statsLabel": "{folders} folders · {convos} conversations",
       "openFolder": "Open Folder",
       "searchPlaceholder": "Search conversations...",
-      "viewFlat": "Flat view",
-      "viewGrouped": "Grouped by folder",
+      "showCompleted": "Show completed conversations",
+      "moreOptions": "More options",
+      "statusRunningBadge": "Running",
+      "statusFailedBadge": "Failed",
+      "conversationCountUnit": "{count, plural, one {# conversation} other {# conversations}}",
+      "emptyFolderHint": "No conversations",
       "noMatchingConversations": "No matching conversations",
       "removeFolderConfirmTitle": "Remove folder from workspace?",
       "removeFolderConfirmDescription": "Remove \"{name}\" from the workspace? Its tabs and terminals will close.",

src/i18n/messages/es.json

@@ -834,8 +834,12 @@
       "statsLabel": "{folders} carpetas · {convos} conversaciones",
       "openFolder": "Abrir carpeta",
       "searchPlaceholder": "Buscar conversaciones...",
-      "viewFlat": "Vista plana",
-      "viewGrouped": "Agrupar por carpeta",
+      "showCompleted": "Mostrar conversaciones completadas",
+      "moreOptions": "Más opciones",
+      "statusRunningBadge": "Ejecutando",
+      "statusFailedBadge": "Fallido",
+      "conversationCountUnit": "{count, plural, one {# conversación} other {# conversaciones}}",
+      "emptyFolderHint": "Sin conversaciones",
       "noMatchingConversations": "No hay conversaciones coincidentes",
       "removeFolderConfirmTitle": "¿Eliminar carpeta del espacio de trabajo?",
       "removeFolderConfirmDescription": "¿Eliminar \"{name}\" del espacio de trabajo? Sus pestañas y terminales se cerrarán.",

src/i18n/messages/fr.json

@@ -834,8 +834,12 @@
       "statsLabel": "{folders} dossiers · {convos} conversations",
       "openFolder": "Ouvrir le dossier",
       "searchPlaceholder": "Rechercher des conversations...",
-      "viewFlat": "Vue à plat",
-      "viewGrouped": "Grouper par dossier",
+      "showCompleted": "Afficher les conversations terminées",
+      "moreOptions": "Plus d'options",
+      "statusRunningBadge": "En cours",
+      "statusFailedBadge": "Échec",
+      "conversationCountUnit": "{count, plural, one {# conversation} other {# conversations}}",
+      "emptyFolderHint": "Aucune conversation",
       "noMatchingConversations": "Aucune conversation correspondante",
       "removeFolderConfirmTitle": "Retirer le dossier de l'espace de travail ?",
       "removeFolderConfirmDescription": "Retirer \"{name}\" de l'espace de travail ? Les onglets et terminaux associés seront fermés.",

src/i18n/messages/ja.json

@@ -834,8 +834,12 @@
       "statsLabel": "{folders} フォルダ · {convos} 会話",
       "openFolder": "フォルダを開く",
       "searchPlaceholder": "会話を検索...",
-      "viewFlat": "フラット表示",
-      "viewGrouped": "フォルダでグループ化",
+      "showCompleted": "完了した会話を表示",
+      "moreOptions": "その他のオプション",
+      "statusRunningBadge": "実行中",
+      "statusFailedBadge": "失敗",
+      "conversationCountUnit": "{count} 件",
+      "emptyFolderHint": "会話がありません",
       "noMatchingConversations": "一致する会話がありません",
       "removeFolderConfirmTitle": "このフォルダをワークスペースから削除しますか？",
       "removeFolderConfirmDescription": "\"{name}\" をワークスペースから削除しますか？関連するタブとターミナルが閉じられます。",

src/i18n/messages/ko.json

@@ -834,8 +834,12 @@
       "statsLabel": "{folders}개 폴더 · {convos}개 대화",
       "openFolder": "폴더 열기",
       "searchPlaceholder": "대화 검색...",
-      "viewFlat": "평면 보기",
-      "viewGrouped": "폴더별 그룹",
+      "showCompleted": "완료된 대화 표시",
+      "moreOptions": "더 많은 옵션",
+      "statusRunningBadge": "실행 중",
+      "statusFailedBadge": "실패",
+      "conversationCountUnit": "{count}개",
+      "emptyFolderHint": "대화 없음",
       "noMatchingConversations": "일치하는 대화가 없습니다",
       "removeFolderConfirmTitle": "이 폴더를 워크스페이스에서 제거하시겠습니까?",
       "removeFolderConfirmDescription": "워크스페이스에서 \"{name}\"을(를) 제거하시겠습니까? 관련 탭과 터미널이 닫힙니다.",

src/i18n/messages/pt.json

@@ -834,8 +834,12 @@
       "statsLabel": "{folders} pastas · {convos} conversas",
       "openFolder": "Abrir pasta",
       "searchPlaceholder": "Buscar conversas...",
-      "viewFlat": "Visualização plana",
-      "viewGrouped": "Agrupar por pasta",
+      "showCompleted": "Mostrar conversas concluídas",
+      "moreOptions": "Mais opções",
+      "statusRunningBadge": "Executando",
+      "statusFailedBadge": "Falhou",
+      "conversationCountUnit": "{count, plural, one {# conversa} other {# conversas}}",
+      "emptyFolderHint": "Sem conversas",
       "noMatchingConversations": "Nenhuma conversa correspondente",
       "removeFolderConfirmTitle": "Remover pasta do espaço de trabalho?",
       "removeFolderConfirmDescription": "Remover \"{name}\" do espaço de trabalho? As abas e terminais relacionados serão fechados.",

src/i18n/messages/zh-CN.json

@@ -834,8 +834,12 @@
       "statsLabel": "{folders} 个文件夹 · {convos} 个会话",
       "openFolder": "打开文件夹",
       "searchPlaceholder": "搜索会话...",
-      "viewFlat": "平铺视图",
-      "viewGrouped": "按文件夹分组",
+      "showCompleted": "显示已完成会话",
+      "moreOptions": "更多选项",
+      "statusRunningBadge": "运行中",
+      "statusFailedBadge": "失败",
+      "conversationCountUnit": "{count} 条",
+      "emptyFolderHint": "暂无会话",
       "noMatchingConversations": "未找到匹配的会话",
       "removeFolderConfirmTitle": "从工作区移除该文件夹？",
       "removeFolderConfirmDescription": "从工作区移除 \"{name}\"？其相关 Tab 与终端将会关闭。",

src/i18n/messages/zh-TW.json

@@ -834,8 +834,12 @@
       "statsLabel": "{folders} 個資料夾 · {convos} 個對話",
       "openFolder": "開啟資料夾",
       "searchPlaceholder": "搜尋對話...",
-      "viewFlat": "平鋪視圖",
-      "viewGrouped": "依資料夾分組",
+      "showCompleted": "顯示已完成對話",
+      "moreOptions": "更多選項",
+      "statusRunningBadge": "運行中",
+      "statusFailedBadge": "失敗",
+      "conversationCountUnit": "{count} 條",
+      "emptyFolderHint": "暫無對話",
       "noMatchingConversations": "找不到符合的對話",
       "removeFolderConfirmTitle": "從工作區移除此資料夾？",
       "removeFolderConfirmDescription": "從工作區移除 \"{name}\"？相關分頁與終端機將會關閉。",