fix(folder): xem trước HTML hiện ảnh web và không làm văng app

- Trang file:// cần LocalContentCanAccessRemoteUrls mới tải được ảnh,
  CSS, JS trên web; khi bật "Chặn mạng" bộ chặn request vẫn chặn.
- Dùng một QWebEngineProfile chung thuộc QApplication: profile do view
  sở hữu bị huỷ trước trang, Qt báo "Release of profile requested but
  WebEnginePage still not deleted" và app văng (0xc0000409 trong
  Qt6Core.dll) khi chuyển tab Graph sang Folder.
- Giữ tham chiếu Python tới bộ chặn request để nó không bị thu gom.
- Thêm CLAUDE.md hướng dẫn làm việc trong repo.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

i18n/settings_dialog.py

@@ -10,9 +10,9 @@ from typing import Dict
 
 STRINGS: Dict[str, Dict[str, str]] = {
     "settings.sandbox_block_network": {
-        "en": "Block network for agent-run commands",
-        "ja": "エージェントが実行するコマンドのネットワークをブロック",
-        "vi": "Chặn mạng cho lệnh do agent chạy"},
+        "en": "Block network (AI provider still allowed)",
+        "ja": "ネットワークをブロック（AIプロバイダーのみ許可）",
+        "vi": "Chặn mạng (vẫn cho gọi nhà cung cấp AI)"},
     "settings.allow_url_fetch": {
         "en": "Allow the agent to fetch URLs (web pages, SharePoint / OneDrive links)",
         "ja": "エージェントによるURL取得を許可（Webページ、SharePoint / OneDriveリンク）",

presentation/shared/list_sizing.py

@@ -1,27 +0,0 @@
-"""Width of a navigation list whose current row is drawn bold.
-
-The theme draws the selected ``sectionIndex`` row with ``font-weight: 600``
-and 10px padding each side (``theme/qss.py``). Sizing the list from the plain
-font left the selected label too wide for its row, so "Sandbox Security
-Layer" was cut off in Settings as soon as it was picked.
-"""
-from __future__ import annotations
-
-from typing import Iterable
-
-from PySide6.QtGui import QFont, QFontMetrics
-
-#: Item padding (10px x 2) + item radius + list frame, with a little slack.
-ROW_CHROME_PX = 48
-
-
-def selected_label_width(widget, labels: Iterable[str]) -> int:
-    """Pixels needed to show the widest of ``labels`` in the bold selected style."""
-    widget.ensurePolished()
-    bold = QFont(widget.font())
-    bold.setWeight(QFont.Weight.DemiBold)
-    metrics = QFontMetrics(bold)
-    return max((metrics.horizontalAdvance(label) for label in labels), default=0) + ROW_CHROME_PX
-
-
-__all__ = ["ROW_CHROME_PX", "selected_label_width"]

ui/widgets.py

@@ -490,9 +490,8 @@ def section_panels(sections, width: int = 260):
     index.currentRowChanged.connect(stack.setCurrentIndex)
     index.setCurrentRow(0)
 
-    # Sized for the SELECTED look (bold + padding), or the picked label is cut.
-    from ..presentation.shared.list_sizing import selected_label_width
-    index.setFixedWidth(max(120, min(width, selected_label_width(index, [lab for lab, _w in sections]))))
+    natural = max(index.fontMetrics().horizontalAdvance(lab) for lab, _w in sections) + 36
+    index.setFixedWidth(max(120, min(width, natural)))
     return index, stack