feat: Add manual OAuth authorization mode for WebUI (#131)

* feat: add manual OAuth flow support in WebUI

* fix: reset add account modal state on close

* feat: display custom API key in startup banner

* fix: move translations to separate files and optimize import API

* fix: remove orphaned model-manager.js and cleanup callback server on manual auth

---------

Co-authored-by: Badri Narayanan S <59133612+badrisnarayanan@users.noreply.github.com>

public/js/translations/en.js

@@ -298,6 +298,24 @@ window.translations.en = {
     quotaDistribution: "Quota Distribution",
     resetsIn: "Resets in {time}",
     noQuotaData: "No quota data available for this account yet.",
+    // Manual OAuth Mode
+    manualMode: "Manual Mode",
+    manualModeDesc: "(for environments where callback cannot reach)",
+    authLinkLabel: "Authorization Link:",
+    linkCopied: "Link copied to clipboard",
+    pasteCallbackLabel: "Paste callback URL or code:",
+    pasteCallbackPlaceholder: "http://localhost:51121/oauth-callback?code=... or 4/0xxx...",
+    completeAuth: "Complete Authorization",
+    authFailed: "Authorization failed",
+    // Import/Export
+    export: "Export",
+    import: "Import",
+    exportAccounts: "Export Accounts",
+    importAccounts: "Import Accounts",
+    exportSuccess: "Exported {count} accounts",
+    exportFailed: "Export failed",
+    importSuccess: "Import complete:",
+    importFailed: "Import failed",
     // UI Elements
     pageTitle: "Antigravity Console",
     live: "Live",

public/js/translations/id.js

@@ -337,6 +337,24 @@ window.translations.id = {
     quotaDistribution: "Distribusi Kuota",
     resetsIn: "Reset dalam {time}",
     noQuotaData: "Data kuota belum tersedia untuk akun ini.",
+    // Manual OAuth Mode
+    manualMode: "Mode Manual",
+    manualModeDesc: "(untuk lingkungan di mana callback tidak bisa dicapai)",
+    authLinkLabel: "Link Otorisasi:",
+    linkCopied: "Link disalin ke clipboard",
+    pasteCallbackLabel: "Tempel callback URL atau kode:",
+    pasteCallbackPlaceholder: "http://localhost:51121/oauth-callback?code=... atau 4/0xxx...",
+    completeAuth: "Selesaikan Otorisasi",
+    authFailed: "Otorisasi gagal",
+    // Import/Export
+    export: "Ekspor",
+    import: "Impor",
+    exportAccounts: "Ekspor Akun",
+    importAccounts: "Impor Akun",
+    exportSuccess: "Berhasil mengekspor {count} akun",
+    exportFailed: "Gagal mengekspor",
+    importSuccess: "Impor selesai:",
+    importFailed: "Gagal mengimpor",
 
     // Completed TODOs
     pageTitle: "Antigravity Console",

public/js/translations/pt.js

@@ -271,6 +271,29 @@ window.translations.pt = {
     gemini1mDesc: "Adiciona sufixo [1m] aos modelos Gemini para suporte a janela de contexto de 1M.",
     gemini1mWarning: "⚠ Contexto grande pode reduzir o desempenho do Gemini-3-Pro.",
     clickToSet: "Clique para configurar...",
+    none: "Nenhum",
+    // Quota Distribution
+    quotaDistribution: "Distribuição de Quota",
+    resetsIn: "Reseta em {time}",
+    noQuotaData: "Dados de quota ainda não disponíveis para esta conta.",
+    // Manual OAuth Mode
+    manualMode: "Modo Manual",
+    manualModeDesc: "(para ambientes onde callback não consegue alcançar)",
+    authLinkLabel: "Link de Autorização:",
+    linkCopied: "Link copiado para a área de transferência",
+    pasteCallbackLabel: "Cole a URL de callback ou código:",
+    pasteCallbackPlaceholder: "http://localhost:51121/oauth-callback?code=... ou 4/0xxx...",
+    completeAuth: "Completar Autorização",
+    authFailed: "Falha na autorização",
+    // Import/Export
+    export: "Exportar",
+    import: "Importar",
+    exportAccounts: "Exportar Contas",
+    importAccounts: "Importar Contas",
+    exportSuccess: "Exportadas {count} contas",
+    exportFailed: "Falha ao exportar",
+    importSuccess: "Importação concluída:",
+    importFailed: "Falha ao importar",
 
     // Account Selection Strategy translations
     accountSelectionStrategy: "Estratégia de Seleção de Conta",

public/js/translations/tr.js

@@ -280,6 +280,24 @@ window.translations.tr = {
     quotaDistribution: "Kota Dağılımı",
     resetsIn: "{time} içinde sıfırlanır",
     noQuotaData: "Bu hesap için henüz kota verisi yok.",
+    // Manual OAuth Mode
+    manualMode: "Manuel Mod",
+    manualModeDesc: "(callback ulaşamadığında kullan)",
+    authLinkLabel: "Yetkilendirme Linki:",
+    linkCopied: "Link panoya kopyalandı",
+    pasteCallbackLabel: "Callback URL veya kodu yapıştır:",
+    pasteCallbackPlaceholder: "http://localhost:51121/oauth-callback?code=... veya 4/0xxx...",
+    completeAuth: "Yetkilendirmeyi Tamamla",
+    authFailed: "Yetkilendirme başarısız",
+    // Import/Export
+    export: "Dışa Aktar",
+    import: "İçe Aktar",
+    exportAccounts: "Hesapları Dışa Aktar",
+    importAccounts: "Hesapları İçe Aktar",
+    exportSuccess: "{count} hesap dışa aktarıldı",
+    exportFailed: "Dışa aktarma başarısız",
+    importSuccess: "İçe aktarma tamamlandı:",
+    importFailed: "İçe aktarma başarısız",
 
     // TODO: Missing translations - Hardcoded strings from HTML
     // pageTitle: "Antigravity Console",

public/js/translations/zh.js

@@ -298,6 +298,24 @@ window.translations.zh = {
     quotaDistribution: "配额分布",
     resetsIn: "{time} 后重置",
     noQuotaData: "暂无此账号的配额数据。",
+    // Manual OAuth Mode
+    manualMode: "手动模式",
+    manualModeDesc: "(当回调无法到达时使用)",
+    authLinkLabel: "授权链接：",
+    linkCopied: "链接已复制到剪贴板",
+    pasteCallbackLabel: "粘贴回调 URL 或授权码：",
+    pasteCallbackPlaceholder: "http://localhost:51121/oauth-callback?code=... 或 4/0xxx...",
+    completeAuth: "完成授权",
+    authFailed: "授权失败",
+    // Import/Export
+    export: "导出",
+    import: "导入",
+    exportAccounts: "导出账号",
+    importAccounts: "导入账号",
+    exportSuccess: "已导出 {count} 个账号",
+    exportFailed: "导出失败",
+    importSuccess: "导入完成：",
+    importFailed: "导入失败",
 
     // TODO: Missing translations - Hardcoded strings from HTML
     // pageTitle: "Antigravity Console",