Add support for loading files from Google Drive

#vibecoded

src/menu/google_drive_menu.tsx

@@ -0,0 +1,59 @@
+import queryString from 'query-string';
+import {FormattedMessage} from 'react-intl';
+import {useNavigate} from 'react-router';
+import {Icon} from 'semantic-ui-react';
+import {
+  googleDriveService,
+  isGoogleDriveConfigured,
+} from '../datasource/google_drive_service';
+import {MenuItem, MenuType} from './menu_item';
+
+interface Props {
+  menuType: MenuType;
+  onTokenAcquired?: () => void;
+}
+
+/**
+ * Component representing the Google Drive menu option.
+ * It handles authenticating the user and launching the Google Picker to select files.
+ */
+export function GoogleDriveMenu(props: Props) {
+  const navigate = useNavigate();
+
+  // Do not render the menu item if Google Drive API credentials are not configured.
+  if (!isGoogleDriveConfigured()) {
+    return null;
+  }
+
+  async function handleClick() {
+    try {
+      // 1. Request access token
+      await googleDriveService.requestToken();
+      if (props.onTokenAcquired) {
+        props.onTokenAcquired();
+      }
+      // 2. Open Google Picker
+      await googleDriveService.showPicker((fileId) => {
+        navigate({
+          pathname: '/view',
+          search: queryString.stringify({
+            source: 'google-drive',
+            fileId,
+          }),
+        });
+      });
+    } catch (err) {
+      console.error('Failed Google Drive login/file picking:', err);
+    }
+  }
+
+  return (
+    <MenuItem onClick={handleClick} menuType={props.menuType}>
+      <Icon name="google drive" />
+      <FormattedMessage
+        id="menu.load_from_google_drive"
+        defaultMessage="Load from Google Drive"
+      />
+    </MenuItem>
+  );
+}