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/features/messages/MessageBubble.tsx

@@ -17,11 +17,26 @@ interface MessageRowProps {
   myUserId: string | null;
   selectMode?: boolean;
   selected?: boolean;
+  /** README §3.5: "选中气泡加 outline:2px solid #1677ff" -- true while this message is the open
+   *  context menu's target. */
+  menuActive?: boolean;
   onToggleSelect?: (seq: number) => void;
   onContextMenu?: (e: React.MouseEvent, msg: StoredMessage) => void;
 }
 
-export function MessageRow({ topic, msg, mine, isGroup, peerName, myUserId, selectMode, selected, onToggleSelect, onContextMenu }: MessageRowProps) {
+export function MessageRow({
+  topic,
+  msg,
+  mine,
+  isGroup,
+  peerName,
+  myUserId,
+  selectMode,
+  selected,
+  menuActive,
+  onToggleSelect,
+  onContextMenu,
+}: MessageRowProps) {
   if (isServerDeleted(msg)) {
     return <div className="py-1 text-center text-xs text-text-tertiary-4">此消息已被删除</div>;
   }
@@ -77,7 +92,7 @@ export function MessageRow({ topic, msg, mine, isGroup, peerName, myUserId, sele
             <div
               className={`px-3.5 py-2.5 text-[15px] leading-[1.55] break-words ${
                 mine ? 'rounded-[12px_4px_12px_12px] bg-bubble-mine' : 'rounded-[4px_12px_12px_12px] bg-white shadow-bubble'
-              } ${isRecalled(msg) ? 'text-text-tertiary-4 italic' : ''}`}
+              } ${isRecalled(msg) ? 'text-text-tertiary-4 italic' : ''} ${menuActive ? 'outline outline-2 outline-offset-2 outline-accent' : ''}`}
             >
               {isRecalled(msg) ? '⚠ 消息已删除' : renderDrafty(msg.content)}
             </div>