feat: GeoScene frontend POC + Docker deploy for remote host

Migrate maps to @geoscene/core, polish monitoring/alerts UX, fix timeline
basemap flicker and district alert regions, and ship compose/nginx Docker
deploy assets with CBPOA_ROOT data mounts.

Co-authored-by: Cursor <cursoragent@cursor.com>

deploy/nginx-cbpoa.conf

@@ -0,0 +1,37 @@
+server {
+    listen 80;
+    server_name _;
+
+    root /var/www/cbpoa;
+    index index.html;
+
+    client_max_body_size 20m;
+
+    gzip on;
+    gzip_types text/plain text/css application/json application/javascript text/xml application/geo+json;
+    gzip_min_length 1000;
+
+    location /api/ {
+        proxy_pass http://127.0.0.1:8000/api/;
+        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;
+        proxy_set_header X-Forwarded-Proto $scheme;
+        proxy_read_timeout 120s;
+    }
+
+    # Gaode basemap proxy (same as Vite /basemap-gaode)
+    location ~ ^/basemap-gaode/(\d+)/(\d+)/(\d+) {
+        proxy_pass https://webrd01.is.autonavi.com/appmaptile?lang=zh_cn&size=1&scale=1&style=8&z=$1&x=$2&y=$3;
+        proxy_set_header Host webrd01.is.autonavi.com;
+        proxy_ssl_server_name on;
+        proxy_hide_header Set-Cookie;
+        expires 1d;
+        add_header Cache-Control "public";
+    }
+
+    location / {
+        try_files $uri $uri/ /index.html;
+    }
+}