370: Fix thumbnail 404 regression in nginx static-file location

[turegjorup]

Refs #370.

Summary

• The regex location ~* \.(jpg|jpeg|png|gif|...) block in infrastructure/nginx/etc/templates/default.conf.template wins over location / for any URL ending in .jpg. It had no try_files directive, so nginx fell back to the default try_files $uri =404. First-time requests to /media/cache/resolve/<filter>/<path>.jpg 404'd without ever calling PHP, breaking LiipImagineBundle thumbnail generation.
• One-line fix: add try_files $uri /index.php$is_args$args; to the static-file location so missing files hand off to Symfony, matching the implicit 2.6.1 behavior where everything flowed through location /.

Why nginx, not PHP

Putting thumbnail resolution into a PHP-layer file_get_contents on the resolve URL would block the response thread on synchronous image processing per item, add per-collection-item latency on serialization, and tightly couple the DTO output layer to image generation. The nginx fallback is request-routed by the proxy, runs once per missing thumbnail (cached on disk thereafter), and keeps the API contract clean.

Test plan

• Rebuild the nginx image from this branch.
• curl -I https://<host>/media/cache/resolve/thumbnail/<path>.jpg returns 302 (was 404).
• Following the redirect returns 200 with Cache-Control: public, immutable.
• A second request to the original resolve URL returns the same redirect; subsequent direct requests to the resolved path hit the disk-cached file.

🤖 Generated with Claude Code