Add frontend service to Docker setup and configure networking

Introduced a new `frontend` service in `docker-compose.yml`, complete with build, healthchecks, and networking. Added a multi-stage Dockerfile for the frontend, a `.dockerignore` file, and a startup script to wait for the backend. Updated Next.js configuration for Docker compatibility and added API type definitions.

frontend/package.json

@@ -6,7 +6,10 @@
     "dev": "next dev",
     "build": "next build",
     "start": "next start",
-    "lint": "next lint"
+    "lint": "next lint",
+    "docker:build": "docker build -t eventspace-frontend .",
+    "docker:run": "docker run -p 3000:3000 eventspace-frontend"
+
   },
   "dependencies": {
     "react": "^19.0.0",