fix(desktop): label the custom provider preset in the active locale

The custom preset showed the catalog's bare English "Custom" in every
language and prefilled it as the config name. It now reads "Custom API"
(自定义模型 API, etc.) on the chip and in the prefilled name.

desktop/src/__tests__/generalSettings.test.tsx

@@ -2392,7 +2392,7 @@ describe('Settings > Providers tab', () => {
     fireEvent.click(addButton)
 
     const dialog = screen.getByRole('dialog')
-    expect(within(dialog).getByLabelText(/Name/i)).toHaveValue('Custom')
+    expect(within(dialog).getByLabelText(/Name/i)).toHaveValue('Custom API')
     expect(within(dialog).getByRole('textbox', { name: /Base URL/i })).toBeEnabled()
 
     const baseUrlInfo = within(dialog).getByRole('button', { name: 'Base URL help' })

desktop/src/i18n/locales/en.ts

@@ -1442,6 +1442,7 @@ Row 9, all 8 cells: continuing from straight down, turning left through lower-le
   'settings.providers.regionChina': 'China mainland',
   'settings.providers.regionGlobal': 'Global',
   'settings.providers.regionCustom': 'Custom',
+  'settings.providers.customPreset': 'Custom API',
   'settings.providers.apiKey': 'API Key',
   'settings.providers.apiKeyKeep': 'API Key (leave blank to keep current)',
   'settings.providers.showApiKey': 'Show API Key',

desktop/src/i18n/locales/jp.ts

@@ -1443,6 +1443,7 @@ export const jp: Record<TranslationKey, string> = {
   'settings.providers.regionChina': '中国本土',
   'settings.providers.regionGlobal': 'グローバル',
   'settings.providers.regionCustom': 'カスタム',
+  'settings.providers.customPreset': 'カスタム API',
   'settings.providers.apiKey': 'API キー',
   'settings.providers.apiKeyKeep': 'API キー（空欄のままにすると現在の値を保持）',
   'settings.providers.showApiKey': 'API キーを表示',

desktop/src/i18n/locales/kr.ts

@@ -1445,6 +1445,7 @@ export const kr: Record<TranslationKey, string> = {
   'settings.providers.regionChina': '중국 본토',
   'settings.providers.regionGlobal': '글로벌',
   'settings.providers.regionCustom': '사용자 지정',
+  'settings.providers.customPreset': '사용자 지정 API',
   'settings.providers.apiKey': 'API 키',
   'settings.providers.apiKeyKeep': 'API 키 (비워 두면 현재 값 유지)',
   'settings.providers.showApiKey': 'API 키 표시',

desktop/src/i18n/locales/zh-TW.ts

@@ -1442,6 +1442,7 @@ export const zh: Record<TranslationKey, string> = {
   'settings.providers.regionChina': '中國大陸',
   'settings.providers.regionGlobal': '海外',
   'settings.providers.regionCustom': '自訂',
+  'settings.providers.customPreset': '自訂模型 API',
   'settings.providers.apiKey': 'API 金鑰',
   'settings.providers.apiKeyKeep': 'API 金鑰（留空保持不變）',
   'settings.providers.showApiKey': '顯示 API 金鑰',

desktop/src/i18n/locales/zh.ts

@@ -1441,6 +1441,7 @@ export const zh: Record<TranslationKey, string> = {
   'settings.providers.regionChina': '中国大陆',
   'settings.providers.regionGlobal': '海外',
   'settings.providers.regionCustom': '自定义',
+  'settings.providers.customPreset': '自定义模型 API',
   'settings.providers.apiKey': 'API 密钥',
   'settings.providers.apiKeyKeep': 'API 密钥（留空保持不变）',
   'settings.providers.showApiKey': '显示 API 密钥',

desktop/src/pages/settings/ProviderSettings.test.tsx

@@ -237,7 +237,19 @@ describe('retired sponsor providers', () => {
       expect(dialog.queryByRole('button', { name: provider.name })).not.toBeInTheDocument()
     }
     expect(dialog.getByRole('button', { name: 'Atlas Cloud' })).toBeInTheDocument()
-    expect(dialog.getByRole('button', { name: 'Custom' })).toBeInTheDocument()
+    expect(dialog.getByRole('button', { name: 'Custom API' })).toBeInTheDocument()
+  })
+
+  it('labels the custom preset in the active locale and prefills that label as the name', async () => {
+    useSettingsStore.setState({ locale: 'zh' })
+    render(<ProviderSettings />)
+    await screen.findByTestId(`provider-${savedProviders[0]!.id}`)
+
+    fireEvent.click(screen.getByRole('button', { name: /添加模型/ }))
+    const dialog = within(screen.getByRole('dialog'))
+    expect(dialog.queryByRole('button', { name: 'Custom' })).not.toBeInTheDocument()
+    fireEvent.click(dialog.getByRole('button', { name: '自定义模型 API' }))
+    expect(dialog.getByLabelText(/配置名称/)).toHaveValue('自定义模型 API')
   })
 
   it.each(savedProviders)('edits and saves an existing $presetId provider without losing its connection', async (provider) => {

desktop/src/pages/settings/ProviderSettings.tsx

@@ -1173,6 +1173,10 @@ function ProviderFormModal({ open, onClose, mode, provider, presets, browserMode
   const initialPreset = provider
     ? availablePresets.find((p) => p.id === provider.presetId) ?? fallbackPreset
     : selectablePresets[0] ?? fallbackPreset
+  // The custom preset's catalog name is a bare English "Custom"; show a localized
+  // label that says what it is for.
+  const presetLabel = (preset: ProviderPreset) =>
+    preset.id === 'custom' ? t('settings.providers.customPreset') : preset.name
   const initialModels = stripModel1mMarkers(provider?.models ?? initialPreset.defaultModels)
   const initialImageGeneration = provider
     ? provider.imageGeneration
@@ -1187,7 +1191,7 @@ function ProviderFormModal({ open, onClose, mode, provider, presets, browserMode
   )
 
   const [selectedPreset, setSelectedPreset] = useState<ProviderPreset>(initialPreset)
-  const [name, setName] = useState(provider?.name ?? initialPreset.name)
+  const [name, setName] = useState(provider?.name ?? presetLabel(initialPreset))
   const [baseUrl, setBaseUrl] = useState(provider?.baseUrl ?? initialPreset.baseUrl)
   // A preset that decides the protocol per model owns this field: the picked value
   // is only the fallback for models no rule matches, so a record carrying a stale
@@ -1349,7 +1353,7 @@ function ProviderFormModal({ open, onClose, mode, provider, presets, browserMode
     settingsJsonUserEditedRef.current = false
     setSelectedPreset(preset)
     setCompatibility(compatibilityForm())
-    setName(preset.name)
+    setName(presetLabel(preset))
     setBaseUrl(preset.baseUrl)
     setImageGeneration({
       enabled: Boolean(preset.defaultImageGeneration),
@@ -1687,14 +1691,14 @@ function ProviderFormModal({ open, onClose, mode, provider, presets, browserMode
   const renderPresetButton = (preset: ProviderPreset) => (
     <SettingsPill
       key={preset.id}
-      aria-label={preset.name}
+      aria-label={presetLabel(preset)}
       className="relative"
       tone="terracotta"
       selected={selectedPreset.id === preset.id}
       onClick={() => handlePresetChange(preset)}
     >
       {preset.id === 'aruhub' && <img src={aruhubLogo} alt="" className="size-4 rounded-[var(--radius-sm)] object-contain" />}
-      {preset.name}
+      {presetLabel(preset)}
       {preset.id === 'aruhub' && <Star size={12} className="fill-[var(--color-warning)] text-[var(--color-warning)]" aria-label={t('settings.providers.sponsor')} />}
       {preset.isNew && (
         <Badge tone="warning" size="xs" className="absolute -right-1 -top-2">