fix: 用 Static 标题栏替代 Textual Header，确保始终显示

- 自定义 #title-bar (dock top, height 1, bold)
- 移除不可靠的 Header widget
- _setup_title 更新 title_bar 内容

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

services/tui_service.py

@@ -7,7 +7,7 @@ import io
 import time
 from textual.app import App
 from textual.containers import Container, ScrollableContainer
-from textual.widgets import Static, Input, Header
+from textual.widgets import Static, Input
 from textual.suggester import Suggester
 
 try:
@@ -546,6 +546,7 @@ class TUIFramework(App):
         self.message_display = MessageDisplay()
         self.system_monitor = SystemMonitor()
         self.plugin_panel = PluginStatusPanel(plugin_service)
+        self.title_bar = Static("🐱 SenSu", id="title-bar")
         self.command_input = None
         self.CSS = self._generate_css()
     
@@ -553,8 +554,13 @@ class TUIFramework(App):
     def _generate_css(self):
         """动态生成 CSS — dock 布局：标题 + 状态栏 + 主内容 + 底部输入"""
         return """
-    Header {
+    #title-bar {
         dock: top;
+        height: 1;
+        padding: 0 1;
+        background: $panel;
+        color: $text;
+        text-style: bold;
     }
 
     #monitor-area {
@@ -591,7 +597,7 @@ class TUIFramework(App):
 
     def compose(self):
         """组合界面 — 标题 + 状态栏 / 主显示区 / 底部输入栏"""
-        yield Header()
+        yield self.title_bar
         yield Container(
             self.system_monitor,
             self.plugin_panel,
@@ -851,20 +857,15 @@ class TuiService:
             name = framework_config.get('name', 'SenSu')
             version = framework_config.get('version', 'Unknown')
             debug_mode = framework_config.get('debug', False)
-            
-            # 构建标题
-            title_parts = [f"🐱 {name} Ver.{version}"]
+
+            title = f"🐱 {name} Ver.{version}"
             if debug_mode:
-                title_parts.append("[DEBUG]")
-            
-            self.tui_app.title = " ".join(title_parts)
-            self.tui_app.sub_title = "Based DreamSu Framework"
-            logger.debug(f"设置TUI标题: {self.tui_app.title}")
-            logger.debug(f"设置TUI副标题: {self.tui_app.sub_title}")
-            
+                title += " [DEBUG]"
+            self.tui_app.title_bar.update(title)
+            logger.debug(f"设置TUI标题: {title}")
+
         except Exception as e:
-            logger.error(f"设置TUI标题时出错: {e}")
-            self.tui_app.title = "🐱 SenSu - Based DreamSu Framework"  # 默认标题    
+            logger.error(f"设置TUI标题时出错: {e}")    
                 
     async def _run_tui(self):
         """运行TUI"""