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

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

public/app.js

@@ -13,6 +13,7 @@ document.addEventListener('alpine:init', () => {
     Alpine.data('accountManager', window.Components.accountManager);
     Alpine.data('claudeConfig', window.Components.claudeConfig);
     Alpine.data('logsViewer', window.Components.logsViewer);
+    Alpine.data('addAccountModal', window.Components.addAccountModal);
 
     // View Loader Directive
     Alpine.directive('load-view', (el, { expression }, { evaluate }) => {