refactor : reorganize infra files into infra/dev and infra/prod

Consolidate Docker, Nginx, and deploy configs from 5 scattered directories
(docker/, deploy/docker/, deploy/nginx/, script/) into a single infra/ tree
with dev/ and prod/ subdirectories. Update all references in docker-compose,
Makefile, CI workflows, Dockerfiles, and documentation.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

infra/prod/nginx-proxy.conf

@@ -0,0 +1,14 @@
+server {
+    listen 80;
+    listen [::]:80;
+    server_name project.malio-dev.fr;
+
+    location / {
+        proxy_pass http://127.0.0.1:8080;
+        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;
+        client_max_body_size 55m;
+    }
+}