feat: improve Google Picker filtering and add i18n for dialog title

- Use .setQuery('.sb3') to filter files in Google Picker
- Add internationalization for picker dialog title
- Add Japanese translation for picker title: "Google ドライブから Scratch 3.0 プロジェクト (.sb3) を選択"
- Pass localized title from HOC to Google Drive API

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <[email protected]>

Author: takaokouji

src/containers/google-drive-loader-hoc.jsx

@@ -35,6 +35,11 @@ const messages = defineMessages({
         id: 'gui.googleDriveLoader.configError',
         defaultMessage: 'Google Drive is not configured. Please contact the administrator.',
         description: 'An error that displays when Google Drive API is not configured.'
+    },
+    pickerTitle: {
+        id: 'gui.googleDriveLoader.pickerTitle',
+        defaultMessage: 'Select a Scratch 3.0 project (.sb3) from Google Drive',
+        description: 'Title for Google Drive file picker dialog.'
     }
 });
 
@@ -79,9 +84,12 @@ const GoogleDriveLoaderHOC = function (WrappedComponent) {
             // Close file menu
             this.props.closeFileMenu();
 
+            // Get localized title
+            const title = this.props.intl.formatMessage(messages.pickerTitle);
+
             // Initialize and show Google Picker
             // Don't show loading modal yet - wait until user selects a file
-            googleDriveAPI.showPicker(this.handlePickerCallback, this.props.locale)
+            googleDriveAPI.showPicker(this.handlePickerCallback, this.props.locale, title)
                 .catch(error => {
                     log.error('Failed to show Google Picker:', error);
                     alert(this.props.intl.formatMessage(messages.authError)); // eslint-disable-line no-alert

src/lib/google-drive-api.js

@@ -113,9 +113,10 @@ class GoogleDriveAPI {
      * Show Google Picker to select a file
      * @param {Function} callback - Called when user selects a file
      * @param {string} locale - Locale code (e.g., 'en', 'ja') for picker UI language
+     * @param {string} title - Title for the picker dialog
      * @returns {Promise<void>} Promise that resolves when picker is shown
      */
-    async showPicker (callback, locale = 'en') {
+    async showPicker (callback, locale = 'en', title = 'Select a Scratch 3.0 project (.sb3) from Google Drive') {
         if (!this.isInitialized) {
             await this.initialize();
         }
@@ -126,21 +127,21 @@ class GoogleDriveAPI {
 
             this.pickerCallback = callback;
 
-            // Create and show picker
+            // Create DocsView with .sb3 query filter
+            const docsView = new window.google.picker.DocsView()
+                .setIncludeFolders(true)
+                .setQuery('.sb3');
+
             const picker = new window.google.picker.PickerBuilder()
-                .addView(
-                    new window.google.picker.DocsView()
-                        .setIncludeFolders(true)
-                    // No MIME type filter - show all files and validate by extension
-                )
+                .addView(docsView)
                 .addView(
                     new window.google.picker.DocsUploadView()
                         .setIncludeFolders(true)
                 )
                 .setOAuthToken(token)
                 .setDeveloperKey(API_KEY)
                 .setCallback(this.handlePickerResponse.bind(this))
-                .setTitle('Select a Scratch 3.0 project (.sb3) from Google Drive')
+                .setTitle(title)
                 .setLocale(locale)
                 .build();
 

src/locales/ja.js

@@ -4,6 +4,7 @@ export default {
     'gui.googleDriveLoader.loadError': 'Google ドライブからプロジェクトの読み込みに失敗しました。',
     'gui.googleDriveLoader.authError': 'Google ドライブの認証に失敗しました。もう一度お試しください。',
     'gui.googleDriveLoader.configError': 'Google ドライブが設定されていません。管理者に連絡してください。',
+    'gui.googleDriveLoader.pickerTitle': 'Google ドライブから Scratch 3.0 プロジェクト (.sb3) を選択',
     'gui.urlLoader.loadError': 'プロジェクトURLの読み込みに失敗しました。',
     'gui.urlLoader.invalidUrl': '有効なScratchプロジェクトURLまたはGoogle DriveのURLを入力してください。',
     'gui.urlLoader.title': 'URLから読み込む',