design: BottomNavigator, AI 버튼 z index 수정

Author: Ludovico7

client/src/components/bottomNavigator/BottomNavigator.style.ts

@@ -7,7 +7,7 @@ export const bottomNavigatorContainer = cx(
   }),
   css({
     display: "flex",
-    zIndex: 1000,
+    zIndex: 1,
     position: "fixed",
     left: "50%",
     bottom: 0,

client/src/features/ai/AIButton.style.ts

@@ -4,7 +4,7 @@ import { glassContainer } from "@styled-system/recipes";
 export const glassEffect = cx(glassContainer({ border: "md" }));
 
 export const floatingButtonContainer = css({
-  zIndex: "50",
+  zIndex: "1",
   position: "fixed",
   right: "24px",
   bottom: "24px",