refactor(ui): 优化 ThemeableStatic 组件重渲染逻辑

- 移除 ThemeableStatic 的 resetKey 属性，避免不必要的重新挂载
- 改用 welcomeNonce 仅触发 PromptInput 等组件重渲染
- 更新 colors-theme 中 codeBlock 和 table 的颜色样式
- MessageView 新增代码段背景渲染支持，提升代码块显示效果
- ThemeableStatic 内部优化渲染函数和 props 比较逻辑，提升性能表现

Author: hqwlkj

src/ui/components/MessageView/index.tsx

@@ -82,6 +82,13 @@ export function MessageView({ message, collapsed, width = 80 }: MessageViewProps
                     </Box>
                   );
                 }
+                if (seg.kind === "code") {
+                  return (
+                    <Box key={i} backgroundColor={theme.codeBlock.background} paddingLeft={1}>
+                      <Text>{seg.body}</Text>
+                    </Box>
+                  );
+                }
                 return <Text key={i}>{seg.body}</Text>;
               })
             : null}

src/ui/components/ThemeableStatic/index.tsx

@@ -21,23 +21,14 @@ type Props<T> = {
 const ThemeableStaticInner = function ThemeableStaticInner<T>({
   items,
   themeVersion: _themeVersion,
-  resetKey,
   children: render,
 }: Props<T>): React.ReactElement {
-  // resetKey 用于 /new 等需要重新挂载的场景
-  // themeVersion 不参与 key，切换主题时历史消息保持原样，新消息用新主题
-  const key = `${resetKey ?? 0}`;
-
   const wrappedRender = useMemo(() => (item: T, index: number) => render(item, index), [render]);
-  return (
-    <Static key={key} items={items}>
-      {wrappedRender}
-    </Static>
-  );
+  return <Static items={items}>{wrappedRender}</Static>;
 };
 
 function propsAreEqual(prev: Props<unknown>, next: Props<unknown>): boolean {
-  return prev.items === next.items && prev.themeVersion === next.themeVersion && prev.resetKey === next.resetKey;
+  return prev.items === next.items && prev.themeVersion === next.themeVersion;
 }
 
 export default React.memo(ThemeableStaticInner, propsAreEqual) as typeof ThemeableStaticInner;

src/ui/theme/colors-theme.ts

@@ -152,10 +152,10 @@ export function buildThemeTokens(
       border: dimHex(fg, 0.7),
     },
     codeBlock: {
-      foreground: fg,
-      background: mode === "dark" ? dimHex(c.Background, 0.15) : dimHex(c.Background, 0.05),
+      foreground: inv,
+      background: dimHex(fg, 0.7),
       border: dimHex(fg, 0.7),
-      title: fg,
+      title: inv,
       lineNumber: c.Gray,
       highlight: mode === "dark" ? "#2d333b" : "#fff8c5",
     },
@@ -187,7 +187,7 @@ export function buildThemeTokens(
       unchecked: dimHex(fg, 0.7),
     },
     table: {
-      border: dimHex(fg, 0.7),
+      border: dimHex(c.AccentYellowDim, 0.7),
       headerForeground: fg,
       headerBackground: dimHex(c.Background, 0.08),
       cellForeground: fg,

src/ui/views/App.tsx

@@ -630,7 +630,8 @@ function App({ projectRoot, initialPrompt, onRestart }: AppProps): React.ReactEl
 
     // Don't clear the screen on resize — Ink handles re-layout naturally.
     // Clearing causes scroll-to-top and flash, especially on tab switch in iTerm2.
-    // Just force ThemeableStatic to remount so Ink recalculates row heights.
+    // Use welcomeNonce to force PromptInput and other components to re-render,
+    // but don't pass it to ThemeableStatic (see layoutResetKey below).
     setWelcomeNonce((n) => n + 1);
     // eslint-disable-next-line react-hooks/exhaustive-deps
   }, [busy, mode, sessionManager, columns]);
@@ -736,7 +737,7 @@ function App({ projectRoot, initialPrompt, onRestart }: AppProps): React.ReactEl
 
   return (
     <Box flexDirection="column" width={screenWidth} minWidth={80} overflowX={"visible"}>
-      <ThemeableStatic items={staticItems} themeVersion={themeVersion} resetKey={welcomeNonce}>
+      <ThemeableStatic items={staticItems} themeVersion={themeVersion}>
         {(item) => {
           if (item.id.startsWith("__welcome__")) {
             return (