feat: Round 5 - Memory Service, Tool Engine, Call Records, Thinking Logs

- Fix: Session history flash (race condition + WS guard)
- Fix: Chat background overlay + sidebar transparency
- Fix: IoT device control (Chinese action names, status field)
- Feat: Independent memory-service (port 8091, 13 endpoints)
- Feat: Independent tool-engine service (port 8092, 13 tools)
- Feat: Tool call logs with paginated DevTools panel
- Feat: Thinking log records with DevTools panel
- Feat: Future development roadmap document
- Chore: Updated .gitignore, go.work, DevTools config
- Chore: 5-service health check, project review docs

frontend/web/src/components/chat/ChatContainer.tsx

@@ -14,7 +14,7 @@ export function ChatContainer() {
   return (
     <div className="flex flex-col h-full overflow-hidden chat-background">
       {/* 状态指示器栏 */}
-      <div className="flex items-center justify-between px-4 py-1.5 border-b border-pink-100 dark:border-pink-900 bg-pink-50/50 dark:bg-pink-950/20 flex-shrink-0">
+      <div className="relative z-10 flex items-center justify-between px-4 py-1.5 border-b border-pink-100 dark:border-pink-900 bg-pink-50/50 dark:bg-pink-950/20 flex-shrink-0">
         <div className="flex items-center gap-2">
           {statusLabel && (
             <span className="text-xs font-medium text-pink-500 dark:text-pink-400 bg-pink-100 dark:bg-pink-900/50 px-2 py-0.5 rounded-full">
@@ -42,12 +42,14 @@ export function ChatContainer() {
       </div>
 
       {/* 消息列表 */}
-      <div className="flex-1 min-h-0 overflow-hidden">
+      <div className="relative z-10 flex-1 min-h-0 overflow-hidden">
         <MessageList messages={messages} isTyping={isTyping} />
       </div>
 
       {/* IoT 状态栏（底部） */}
-      <IoTStatusBar />
+      <div className="relative z-10">
+        <IoTStatusBar />
+      </div>
     </div>
   );
 }