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>

.gitignore

@@ -28,5 +28,5 @@
 ###< ide ###
 
 ###> docker local ###
-docker/.env.docker.local
+infra/dev/.env.docker.local
 ###< docker local ###