Update section-header style

Author: ajhai

llmstack/client/src/index.css

@@ -15,6 +15,7 @@ code {
 
 .section-header {
   text-align: left;
+  margin: 0 !important;
   margin-bottom: 10px;
   padding: 5px 10px;
   font-weight: 600 !important;

llmstack/client/src/pages/AppStudio.jsx

@@ -73,7 +73,7 @@ const AppStudioPage = () => {
         <AppTemplatesContainer />
       </Box>
       <Box style={{ marginBottom: "20px" }} className="your-apps">
-        <Typography variant="h6" className="section-header">
+        <Typography variant="h5" className="section-header">
           Your Apps
           <br />
           <Typography variant="caption" sx={{ color: "#666" }}>