chore: initial project setup with backend, frontend, and infrastructure

Add complete NexaPantry application structure including:
- Docker Compose configuration with PostgreSQL, Redis, FastAPI backend, worker, frontend and Caddy
- Environment configuration template with database, auth, and service settings
- GitHub Actions CI workflow for backend/frontend linting, testing, auditing and Docker builds
- AGPL-3.0 license and comprehensive README with setup, development, and security documentation
- Backend

frontend/nginx.conf

@@ -0,0 +1,26 @@
+worker_processes auto;
+pid /tmp/nginx.pid;
+
+events { worker_connections 1024; }
+
+http {
+  include /etc/nginx/mime.types;
+  server_tokens off;
+  access_log off;
+
+  server {
+    listen 8080;
+    root /usr/share/nginx/html;
+    index index.html;
+
+    location / {
+      try_files $uri $uri/ /index.html;
+    }
+
+    location ~* \.(js|css|png|jpg|jpeg|gif|svg|webp|woff2)$ {
+      expires 30d;
+      add_header Cache-Control "public, immutable";
+      try_files $uri =404;
+    }
+  }
+}