fix(docker): Update nginx context path for git-based deployments

Changed from ../smoothschedule-frontend to ../frontend to match
the git repository structure.

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

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

smoothschedule/docker-compose.production.yml

@@ -48,7 +48,7 @@ services:
 
   nginx:
     build:
-      context: ../smoothschedule-frontend
+      context: ../frontend
       dockerfile: Dockerfile.prod
       args:
         VITE_API_URL: https://api.smoothschedule.com