Add comprehensive Kubernetes migration guide from local to production

This commit adds complete documentation and tooling for migrating from
local development (Kind/Colima on macOS) to production deployment
(MicroK8s on Ubuntu VPS at Clouding.io).

Documentation added:
- K8S-MIGRATION-GUIDE.md: Comprehensive step-by-step migration guide
  covering all phases from VPS setup to post-deployment operations
- MIGRATION-CHECKLIST.md: Quick reference checklist for migration tasks
- MIGRATION-SUMMARY.md: High-level overview and key changes summary

Configuration updates:
- Added storage-patch.yaml for MicroK8s storage class compatibility
  (changes from 'standard' to 'microk8s-hostpath')
- Updated prod/kustomization.yaml to include storage patch

Helper scripts:
- deploy-production.sh: Interactive deployment script with validation
- tag-and-push-images.sh: Automated image tagging and registry push
- backup-databases.sh: Database backup script for production

Key differences addressed:
- Ingress: MicroK8s addon vs custom NGINX
- Storage: MicroK8s hostpath vs Kind standard storage
- Registry: Container registry configuration for production
- SSL: Let's Encrypt production certificates
- Domains: Real domain configuration vs localhost
- Resources: Production-grade resource limits and scaling

The migration guide covers:
- VPS setup and MicroK8s installation
- Configuration adaptations required
- Container registry setup options
- SSL certificate configuration
- Monitoring and backup setup
- Troubleshooting common issues
- Security hardening checklist
- Rollback procedures

All existing Kubernetes manifests remain unchanged and compatible.

infrastructure/kubernetes/overlays/prod/kustomization.yaml

@@ -11,6 +11,9 @@ resources:
   - prod-ingress.yaml
   - prod-configmap.yaml
 
+patchesStrategicMerge:
+  - storage-patch.yaml
+
 labels:
   - includeSelectors: true
     pairs:

infrastructure/kubernetes/overlays/prod/storage-patch.yaml

@@ -0,0 +1,12 @@
+apiVersion: v1
+kind: PersistentVolumeClaim
+metadata:
+  name: model-storage
+  namespace: bakery-ia
+spec:
+  storageClassName: microk8s-hostpath  # MicroK8s storage class
+  accessModes:
+    - ReadWriteOnce
+  resources:
+    requests:
+      storage: 50Gi  # Increased for production (adjust based on your needs)