refactor(web): unify settings dialogs into single dialog with sidebar

Merge API integration, model settings, account settings and storage
analysis into one SettingsDialog with a shadcn inner sidebar for
section switching. Preserve existing ?action= query-param deep links
(showModelSettings / showAccountSettings / showApiIntegrationSettings /
showStorageAnalysis) by mapping each to a section. Extract reusable
panels and keep ModelsDialog as a thin wrapper for the dynamic-form
model picker.

web/src/i18n/locales/en-US.ts

@@ -1386,6 +1386,9 @@ const enUS = {
     boxSessionCreated: 'Created',
     boxSessionLastUsed: 'Last used',
   },
+  settingsDialog: {
+    title: 'Settings',
+  },
   storageAnalysis: {
     title: 'Storage Analysis',
     description: 'Inspect storage usage and cleanup candidates',

web/src/i18n/locales/es-ES.ts

@@ -1419,6 +1419,9 @@ const esES = {
     boxSessionCreated: 'Creado',
     boxSessionLastUsed: 'Último uso',
   },
+  settingsDialog: {
+    title: 'Configuración',
+  },
   storageAnalysis: {
     title: 'Análisis de almacenamiento',
     description:

web/src/i18n/locales/ja-JP.ts

@@ -1392,6 +1392,9 @@ const jaJP = {
     boxSessionCreated: '作成日時',
     boxSessionLastUsed: '最終使用',
   },
+  settingsDialog: {
+    title: '設定',
+  },
   storageAnalysis: {
     title: 'ストレージ分析',
     description: 'ストレージ使用量とクリーンアップ候補を確認します',

web/src/i18n/locales/ru-RU.ts

@@ -1395,6 +1395,9 @@ const ruRU = {
     boxSessionCreated: 'Создано',
     boxSessionLastUsed: 'Последнее использование',
   },
+  settingsDialog: {
+    title: 'Настройки',
+  },
   storageAnalysis: {
     title: 'Анализ хранилища',
     description: 'Проверьте использование хранилища и кандидатов на очистку',

web/src/i18n/locales/th-TH.ts

@@ -1364,6 +1364,9 @@ const thTH = {
     boxSessionCreated: 'สร้างเมื่อ',
     boxSessionLastUsed: 'ใช้ล่าสุด',
   },
+  settingsDialog: {
+    title: 'การตั้งค่า',
+  },
   storageAnalysis: {
     title: 'วิเคราะห์พื้นที่จัดเก็บ',
     description: 'ตรวจสอบการใช้พื้นที่จัดเก็บและรายการที่สามารถล้างได้',

web/src/i18n/locales/vi-VN.ts

@@ -1388,6 +1388,9 @@ const viVN = {
     boxSessionCreated: 'Đã tạo',
     boxSessionLastUsed: 'Lần cuối sử dụng',
   },
+  settingsDialog: {
+    title: 'Cài đặt',
+  },
   storageAnalysis: {
     title: 'Phân tích lưu trữ',
     description: 'Kiểm tra dung lượng lưu trữ và các mục có thể dọn dẹp',

web/src/i18n/locales/zh-Hans.ts

@@ -1328,6 +1328,9 @@ const zhHans = {
     boxSessionCreated: '创建时间',
     boxSessionLastUsed: '最后使用',
   },
+  settingsDialog: {
+    title: '设置',
+  },
   storageAnalysis: {
     title: '存储分析',
     description: '查看存储占用和可清理文件',

web/src/i18n/locales/zh-Hant.ts

@@ -1327,6 +1327,9 @@ const zhHant = {
     boxSessionCreated: '建立時間',
     boxSessionLastUsed: '最後使用',
   },
+  settingsDialog: {
+    title: '設定',
+  },
   storageAnalysis: {
     title: '儲存分析',
     description: '查看儲存占用和可清理檔案',