feat: Add Docker config, Gitea workflow, and map improvements

- Add Dockerfile, nginx.conf, docker-compose.yml
- Add Gitea Actions workflow
- Improve map mobile UX (safe area, no pull-to-refresh)
- Persist map state (zoom, center, layer) to localStorage
- Add Google Hybrid map layer
- Configure Vite for Cloudflare tunnel

nginx.conf

@@ -0,0 +1,15 @@
+server {
+    listen       80;
+    server_name  localhost;
+
+    location / {
+        root   /usr/share/nginx/html;
+        index  index.html index.htm;
+        try_files $uri $uri/ /index.html;
+    }
+
+    error_page   500 502 503 504  /50x.html;
+    location = /50x.html {
+        root   /usr/share/nginx/html;
+    }
+}