fix: 回到 grid 布局 + 顶部留空行 — 5行: 空/标题/状态栏/主区/输入

grid-rows: 1 1 auto 1fr 3
- Row 1: 空白行
- Row 2: 标题栏 (Static, bold)
- Row 3: 状态栏 (auto 高度)
- Row 4: 主显示区 (1fr 填满剩余)
- Row 5: 输入栏 (固定3行)

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

services/tui_service.py

@@ -552,11 +552,15 @@ 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"""
+        """动态生成 CSS — grid 布局：空行 + 标题 + 状态栏 + 主内容 + 底部输入"""
         return """
+    Screen {
+        layout: grid;
+        grid-size: 1 5;
+        grid-rows: 1 1 auto 1fr 3;
+    }
+
     #title-bar {
-        dock: top;
-        height: 1;
         padding: 0 1;
         background: $panel;
         color: $text;
@@ -564,18 +568,9 @@ class TUIFramework(App):
     }
 
     #monitor-area {
-        dock: top;
-        padding: 1 1 0 1;
+        padding: 0 1;
         background: $panel;
         color: $text;
-        height: auto;
-    }
-
-    #input-area {
-        dock: bottom;
-        padding: 0 1;
-        height: 3;
-        align: center bottom;
     }
 
     #main-area {
@@ -584,6 +579,10 @@ class TUIFramework(App):
         border: solid $primary;
     }
 
+    #input-area {
+        padding: 0 1;
+    }
+
     ScrollableContainer {
         scrollbar-color: #666 #222;
         scrollbar-color-hover: #888 #333;
@@ -596,14 +595,15 @@ 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 self.title_bar
-        yield Container(
+        """组合界面 — 空行 + 标题 + 状态栏 + 主显示区 + 底部输入"""
+        yield Static("")                 # Row 1: blank
+        yield self.title_bar            # Row 2: title
+        yield Container(                # Row 3: monitor
             self.system_monitor,
             self.plugin_panel,
             id="monitor-area",
         )
-        yield ScrollableContainer(
+        yield ScrollableContainer(      # Row 4: main (1fr)
             self.log_display,
             id="main-area",
         )
@@ -613,7 +613,7 @@ class TUIFramework(App):
             suggester=self.command_suggester,
             id="command-input",
         )
-        yield Container(
+        yield Container(                # Row 5: input (3 rows)
             self.command_input,
             id="input-area",
         )