fix: remove excessive padding between status bar and footer controls

Removed 24px bottom padding from footerContainer that was creating a large
gap between AgentStatusBar and the GlobalFooter controls below.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

packages/app/src/app/agent/[id].tsx

@@ -103,7 +103,6 @@ const styles = StyleSheet.create((theme) => ({
   },
   footerContainer: {
     backgroundColor: theme.colors.background,
-    paddingBottom: theme.spacing[6],
   },
   errorContainer: {
     flex: 1,