Ship production optimization M1-M12.5A: queues, metrics, HTTP observability, and vector search reliability.

Keep similar-ai from tripping the global circuit on a lone URL 502, clamp Qdrant search to 100, and add Server-Timing plus slow-request logging. Studio shared props, Academy S3 exists caching, heat chunking, and Redis/scheduler hygiene stay in this rollout.

deploy/nginx/conf.d/skinbase-perf-log-format.conf

@@ -0,0 +1,23 @@
+# M12 — structured HTTP performance log format.
+# Install into /etc/nginx/conf.d/ (already included from nginx.conf http {}).
+# Do not replace the existing combined access log.
+# Activate with a second access_log on the Skinbase server block.
+#
+# Variables validated against nginx/1.26.3 on server3.
+# $uri is used (not $request_uri) so query strings are not logged.
+# No $remote_addr, cookies, or Authorization.
+
+log_format skinbase_perf escape=json
+    '{"time":"$time_iso8601",'
+    '"host":"$host",'
+    '"method":"$request_method",'
+    '"uri":"$uri",'
+    '"status":$status,'
+    '"request_time":$request_time,'
+    '"upstream_response_time":"$upstream_response_time",'
+    '"upstream_connect_time":"$upstream_connect_time",'
+    '"upstream_header_time":"$upstream_header_time",'
+    '"bytes":$body_bytes_sent,'
+    '"request_length":$request_length,'
+    '"content_type":"$sent_http_content_type",'
+    '"cache":"$upstream_cache_status"}';

deploy/nginx/sitemaps.conf

@@ -1,38 +1,47 @@
 # ---------------------------------------------------------------------------
 # Nginx static sitemap file serving
 # ---------------------------------------------------------------------------
-# Include this snippet inside your `server {}` block BEFORE the main
-# `location /` (or `location ~ \.php$`) block so nginx serves the pre-built
-# static XML files without ever touching PHP/FPM.
+# Compatible with the production skinbase.org vhost, which has NO named
+# location @php. Laravel is already wired as:
 #
-# The GenerateSitemapsCommand writes these files on a schedule (every 6 h):
-#   public/sitemap.xml            <- root sitemap index
-#   public/sitemaps/{name}.xml    <- per-family / per-shard documents
+#   location / {
+#       try_files $uri $uri/ /index.php?$query_string;
+#   }
+#   location = /index.php {
+#       fastcgi_pass unix:/run/php/php8.4-fpm-skinbase.sock;
+#       ...
+#   }
 #
-# When a file has not been generated yet (first deploy, cold start) the
-# request falls through to @php and Laravel's SitemapController builds it
-# live on the first hit.
+# Do not add `try_files ... @php` — that named location does not exist on
+# server3 and nginx -t / runtime would fail (or 500) when the static file
+# is missing.
+#
+# GenerateSitemapsCommand writes:
+#   public/sitemaps/index.xml     <- canonical generated root index
+#   public/sitemaps/sitemap.xml   <- legacy filename (best-effort)
+#   public/sitemap.xml            <- legacy $uri (often unwritable on prod)
+#   public/sitemaps/{name}.xml    <- child / shard documents
+#
+# Place these location blocks BEFORE `location /` is not required if they are
+# more specific (`=` and regex), but they must remain inside the 443 server.
 # ---------------------------------------------------------------------------
 
 # Root sitemap index
 location = /sitemap.xml {
-    # Serve the static file if it exists; otherwise fall through to PHP.
-    try_files $uri @php;
+    # Prefer the scheduler-writable generated index. Fall back to the legacy
+    # sitemaps/sitemap.xml, then Laravel front controller (not @php).
+    try_files /sitemaps/index.xml /sitemaps/sitemap.xml /index.php?$query_string;
 
-    # Instruct downstream caches / crawlers how long the file is fresh.
-    add_header Cache-Control "public, max-age=21600" always;  # 6 h
+    add_header Cache-Control "public, max-age=21600" always;
     add_header Content-Type  "application/xml; charset=UTF-8" always;
-
-    # Optional: let nginx set a strong ETag automatically (default behaviour).
     etag on;
 }
 
 # Per-family / per-shard sitemap documents
 location ~ ^/sitemaps/[A-Za-z0-9_\-]++\.xml$ {
-    try_files $uri @php;
+    try_files $uri /index.php?$query_string;
 
-    add_header Cache-Control "public, max-age=21600" always;  # 6 h
+    add_header Cache-Control "public, max-age=21600" always;
     add_header Content-Type  "application/xml; charset=UTF-8" always;
-
     etag on;
 }

deploy/nginx/skinbase-vhost-performance-log.snippet

@@ -0,0 +1,16 @@
+# M12 — add INSIDE the HTTPS server { } for skinbase.org, next to the
+# existing combined access_log. Keep the original line unchanged.
+#
+#     access_log /var/log/nginx/skinbase.org-access.log;
+#     access_log /var/log/nginx/skinbase-performance.log skinbase_perf;
+#
+# Locations that already set `access_log off;` (static assets, /photo/*.jpg)
+# remain excluded from both logs.
+# File is created as 0640 www-data adm by nginx; logrotate /var/log/nginx/*.log
+# already rotates it (daily, 14 copies).
+#
+# After install:
+#   sudo nginx -t && sudo systemctl reload nginx
+# Never `restart` nginx for this change.
+
+access_log /var/log/nginx/skinbase-performance.log skinbase_perf;