feat(docker): add /peregrine/ base-path routing in nginx

Adds location blocks for /peregrine/assets/ and /peregrine/ so the SPA
works correctly when accessed via a Caddy prefix that does not strip the
path (e.g. direct host access without reverse proxy stripping).

docker/web/nginx.conf

@@ -22,6 +22,19 @@ server {
         add_header Cache-Control "public, immutable";
     }
 
+    # Handle /peregrine/ base path — used when accessed directly (no Caddy prefix stripping).
+    # ^~ blocks regex location matches so assets at /peregrine/assets/... are served correctly.
+    location ^~ /peregrine/assets/ {
+        alias /usr/share/nginx/html/assets/;
+        expires 1y;
+        add_header Cache-Control "public, immutable";
+    }
+
+    location /peregrine/ {
+        alias /usr/share/nginx/html/;
+        try_files $uri $uri/ /index.html;
+    }
+
     # SPA fallback — must come after API and assets
     location / {
         try_files $uri $uri/ /index.html;