feat(lab-04): complete Phase 5 - Storage & S3 lab

Phase Plan:
- 05-PLAN.md: Combined execution plan for efficiency
- 05-RESEARCH.md: Domain research on volumes and MinIO

Test Scripts (4):
- 01-volumes-test.sh: Volume persistence verification
- 02-minio-test.sh: MinIO S3 API testing
- 03-persistence-test.sh: Database persistence verification
- 99-final-verification.sh: End-to-end verification

Documentation (6 files):
Tutorial: Docker volumes, MinIO S3
How-to: Manage volumes
Reference: Volume syntax
Explanation: Storage↔S3 parallels

Infrastructure:
- docker-compose.yml: MinIO S3 + PostgreSQL + test container
- Named volumes: minio-data, db-data, test-data (INF-04 compliant)

Key concepts:
- Named volumes = EBS volumes
- MinIO = S3 bucket (100% API compatible)
- Data persistence across container lifecycle

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

labs/lab-04-storage/explanation/storage-s3-parallels.md

@@ -0,0 +1,63 @@
+# Explanation: Parallelismi Storage Docker ↔ AWS
+
+## Core Concepts
+
+### Docker Named Volume = EBS Volume
+
+| Aspect | Docker | AWS EBS |
+|--------|--------|---------|
+| Creation | docker volume create | aws ec2 create-volume |
+| Lifecycle | Indipendent dal container | Indipendente dall'istanza |
+| Persistence | Sopravvive a docker rm | Sopravvive a ec2 terminate |
+| Mount | volumes: section in compose | Attach to /dev/sdX |
+| Backup | docker run --rm tar | EBS snapshots |
+
+### MinIO = S3
+
+| Aspect | MinIO | AWS S3 |
+|--------|-------|--------|
+| API | 100% S3 compatible | Native S3 |
+| Endpoint | http://localhost:9000 | https://s3.amazonaws.com |
+| Pricing | Free (self-hosted) | Pay-per-use |
+| Use case | Local dev/test | Production |
+
+## Storage Architecture Patterns
+
+### Database with Persistent Storage
+**Locale:**
+```yaml
+db:
+  image: postgres
+  volumes:
+    - db-data:/var/lib/postgresql/data
+```
+**Cloud:** RDS con EBS storage
+
+### Object Storage
+**Locale:**
+```yaml
+minio:
+  image: minio/minio
+  volumes:
+    - minio-data:/data
+```
+**Cloud:** S3 bucket
+
+## Key Differences
+
+1. **Scope:** Volumes = single host, EBS = AZ-wide
+2. **Performance:** Local filesystem vs network storage
+3. **Backup:** tar vs EBS snapshots
+4. **Scaling:** Manual vs S3 infinite scale
+
+## When to Use What
+
+| Use Case | Locale | Cloud |
+|----------|--------|-------|
+| Dev database | PostgreSQL + Volume | RDS |
+| File storage | Volume | EFS |
+| Objects | MinIO | S3 |
+| Backup | tar to host | S3 Glacier |
+
+## Conclusion
+Docker volumes e MinIO seguono gli stessi principi di EBS e S3, permettendoti di praticare localmente prima di deployare in cloud.