Add Docker, Woodpecker CI/CD, and dev proxy setup

- Add multi-stage Dockerfile (Vite build → Nginx serve)
- Add nginx.conf: serves SPA, proxies /api/ to yugioh-api:3000
- Add .woodpecker.yml pipeline (build + deploy on yugioh network, port 8041)
- Add .dockerignore
- Add .env.example with VITE_API_URL
- Update .gitignore to exclude .env files
- Update vite.config.js: proxy /api to backend in dev via VITE_API_URL
- Fix git remote push URLs (were pointing at Dashboard repo)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

nginx.conf

@@ -0,0 +1,19 @@
+server {
+    listen 80;
+    root /usr/share/nginx/html;
+    index index.html;
+
+    # Proxy API calls to the yugioh-api container (strips /api prefix)
+    location /api/ {
+        proxy_pass http://yugioh-api:3000/;
+        proxy_http_version 1.1;
+        proxy_set_header Host $host;
+        proxy_set_header X-Real-IP $remote_addr;
+        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
+    }
+
+    # SPA fallback
+    location / {
+        try_files $uri $uri/ /index.html;
+    }
+}