fix(web): code review round 1 remaining UI fixes

- EmojiPanel: add missing 手势/物品 categories, 12-column grid per README §3.3
- DetailColumn: add 投诉举报 row, real ID/region/签名 via new getUserProfile
  API, chevron_right icons now use --color-icon-arrow token (were tertiary
  text color), regroup rows so dividers only sit between sections not every
  row (matches design-code reference exactly)
- MessageBubble/ConversationView: right-clicked message bubble now gets the
  spec's outline while its context menu is open
- ChatListColumn/AppShell: pinned 系统消息/文件助手 rows using confirmed
  bootstrap entries/entry_badges topic names ("sys"/"slf"); route to the
  existing SectionPlaceholder pattern since their own dedicated layouts are
  Phase 8, not built yet

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

web/src/App.tsx

@@ -41,6 +41,7 @@ const router = createBrowserRouter([
           { path: 'contacts', element: <SectionPlaceholder title="通讯录" /> },
           { path: 'favorites', element: <SectionPlaceholder title="我的收藏" /> },
           { path: 'files', element: <SectionPlaceholder title="文件助手" /> },
+          { path: 'chat/system', element: <SectionPlaceholder title="系统消息" /> },
           { path: 'calls', element: <SectionPlaceholder title="通话记录" /> },
           { path: 'settings', element: <SectionPlaceholder title="设置" /> },
         ],