修复自绘标题栏让位后底部内容超出可视框

window-chrome 下 launcher-main 移除旧版悬浮账户条的 42px padding-bottom，页面容器填满内容区。

首页根容器统一按 platform-theme 覆盖高度与内部滚动，覆盖 h-screen 与 h-[calc] 变体，避免高度基于视口导致底部溢出。

固定弹层样式静态守门补充 launcher-main 与首页容器断言。

apps/ai-game-creator-shell/src/styles.css

@@ -304,21 +304,13 @@ body {
 .window-chrome__content > .launcher-shell .launcher-main {
   height: 100%;
   min-height: 0;
+  padding-bottom: 0;
 }
 
 .window-chrome__content
   > .launcher-shell
   .launcher-main
-  > .platform-theme.min-h-screen {
-  height: 100%;
-  min-height: 0;
-  overflow: auto;
-}
-
-.window-chrome__content
-  > .launcher-shell
-  .launcher-main
-  > .platform-theme.h-screen {
+  > .platform-theme {
   height: 100%;
   min-height: 0;
   overflow: auto;

apps/ai-game-creator-shell/tests/appSurface/runtime-settings.suite.ts

@@ -33,6 +33,9 @@ export function registerAgentStatusDerivationTests() {
     expect(styles).toContain('.launcher-dialog-backdrop {');
     expect(styles).toContain('.game-approval-backdrop {');
     expect(styles).toContain('.gdd-approval-card__dialog-backdrop {');
+    expect(styles).toContain('> .launcher-shell .launcher-main {');
+    expect(styles).toContain('padding-bottom: 0;');
+    expect(styles).toContain('> .platform-theme {');
   });
 
   it('derives agent card status from the latest run trace step', () => {