feat(deploy): full one-line install with search API

Bundle static site, FastAPI search, nginx proxy, and systemd unit so
a fresh Ubuntu VPS can run curl install.sh and get /search working.

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

nginx/domain-web-api.conf

@@ -0,0 +1,11 @@
+# Domain Web API reverse proxy (included from domain-web.conf)
+location /api/ {
+    proxy_pass http://127.0.0.1:8081;
+    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 300s;
+    proxy_connect_timeout 60s;
+}