Add self-contained Docker Compose stacks for pivoine.art infrastructure

Migrated 11 services from monolithic docker-compose project into independent stacks,
each with dedicated databases, minimal .env configuration, and bind-mount data volumes.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

.gitignore

@@ -0,0 +1,3 @@
+.claude
+.env
+*.sql