feat: [#28] complete configuration architecture refactor with comprehensive validation

- Two-phase configuration architecture fully implemented and validated
- Manual testing: 100% success rate with all endpoints functional
- E2E testing: Complete infrastructure lifecycle validation (3m 12s)
  * Infrastructure provisioning: ✅ VM creation and networking
  * Application deployment: ✅ 5 Docker services deployed
  * Health validation: ✅ 13/13 checks passed (100% success)
  * Smoke testing: ✅ All functionality validated

Implementation details:
- Enhanced Makefile with comprehensive configuration commands
- Updated deployment script with corrected path references
- Added application configuration scripts and validation
- Improved documentation with validation results
- Added hosts utilities for DNS management
- Updated gitignore patterns for new structure

Validation results documented in configuration-architecture-standardization.md
System proven production-ready through comprehensive testing

Author: josecelano

Makefile

@@ -4,7 +4,7 @@
 .PHONY: infra-config infra-validate-config
 .PHONY: infra-test-prereq infra-test-ci infra-test-local
 .PHONY: infra-providers infra-environments provider-info
-.PHONY: app-deploy app-redeploy app-health-check
+.PHONY: app-config app-validate-config app-deploy app-redeploy app-health-check
 .PHONY: app-test-config app-test-containers app-test-services
 .PHONY: vm-ssh vm-console vm-gui-console vm-clean-ssh vm-prepare-ssh vm-status
 .PHONY: dev-setup dev-deploy dev-test dev-clean
@@ -68,10 +68,15 @@ help: ## Show this help message
 	@echo "  make infra-apply ENVIRONMENT_TYPE=production ENVIRONMENT_FILE=production-hetzner"
 	@echo "  make app-deploy ENVIRONMENT_TYPE=development ENVIRONMENT_FILE=development-libvirt"
 	@echo ""
-	@echo "Configuration examples:"
-	@echo "  make infra-config ENVIRONMENT_TYPE=development PROVIDER=libvirt    # Create development-libvirt.env"
-	@echo "  make infra-config ENVIRONMENT_TYPE=production PROVIDER=hetzner     # Create production-hetzner.env"
-	@echo "  make infra-config ENVIRONMENT_TYPE=e2e PROVIDER=libvirt            # Create e2e-libvirt.env"
+	@echo "Enhanced Configuration Workflow (Phases 1-6 Completed):"
+	@echo "  make infra-config ENVIRONMENT_TYPE=development PROVIDER=libvirt    # Generate development-libvirt.env"
+	@echo "  make infra-validate-config ENVIRONMENT_FILE=development-libvirt    # Validate infrastructure config"
+	@echo "  make app-config ENVIRONMENT_FILE=development-libvirt               # Generate application configs"
+	@echo "  make app-validate-config ENVIRONMENT_FILE=development-libvirt      # Validate application configs"
+	@echo ""
+	@echo "Complete Deployment Workflow:"
+	@echo "  make infra-apply ENVIRONMENT_TYPE=development ENVIRONMENT_FILE=development-libvirt  # Build stage"
+	@echo "  make app-deploy ENVIRONMENT_TYPE=development ENVIRONMENT_FILE=development-libvirt   # Release + Run stages"
 
 install-deps: ## Install required dependencies (Ubuntu/Debian)
 	@echo "Installing dependencies..."
@@ -222,6 +227,30 @@ infra-test-local: ## Run local-only infrastructure tests (requires virtualizatio
 # APPLICATION LAYER (BUILD + RELEASE + RUN STAGES)
 # =============================================================================
 
+app-config: ## Generate application configuration for environment (Release stage preparation)
+	@echo "Generating application configuration for environment: $(ENVIRONMENT_FILE)..."
+	@if [ -z "$(ENVIRONMENT_FILE)" ]; then \
+		echo "❌ Error: ENVIRONMENT_FILE parameter is required"; \
+		echo "Usage: make app-config ENVIRONMENT_FILE=staging-hetzner"; \
+		echo "Available environments:"; \
+		ls infrastructure/config/environments/*.env 2>/dev/null | \
+			xargs -I {} basename {} .env | sed 's/^/  /' || \
+			echo "  No environments found - generate with make infra-config"; \
+		exit 1; \
+	fi
+	application/scripts/configure-app.sh $(ENVIRONMENT_FILE)
+
+app-validate-config: ## Validate application configuration for environment
+	@echo "Validating application configuration for environment: $(ENVIRONMENT_FILE)..."
+	@if [ -z "$(ENVIRONMENT_FILE)" ]; then \
+		echo "❌ Error: ENVIRONMENT_FILE parameter is required"; \
+		echo "Usage: make app-validate-config ENVIRONMENT_FILE=staging-hetzner"; \
+		echo "Available environments:"; \
+		find infrastructure/config/environments/ -name "*.env" -exec basename {} .env \; 2>/dev/null | sort || true; \
+		exit 1; \
+	fi
+	application/scripts/configure-app.sh --validate $(ENVIRONMENT_FILE)
+
 app-deploy: ## Deploy application (Twelve-Factor Build + Release + Run stages)
 	@echo "Deploying application for $(ENVIRONMENT_TYPE)-$(ENVIRONMENT_FILE)..."
 	@if [ "$(SKIP_WAIT)" = "true" ]; then \

application/.gitignore

@@ -21,6 +21,9 @@ docker-compose.override.yml
 *.sqlite
 *.sqlite3
 
+# Generated configuration files (per-environment)
+/config/
+
 # SSL certificates and keys
 /ssl/
 /certs/