feat: [#332] add DNS setup reminder in provision command

[josecelano]

Overview

Implements #332 - Display a DNS setup reminder after successful provisioning when custom domains are configured. This helps users remember to update their DNS records to point to the server IP address.

Changes

• Add DnsReminderView: New presentation view with conditional rendering based on domain presence
• Add DnsReminderData: DTO for transferring view data (instance IP and domains list)
• Integrate DNS reminder: Display in provision controller workflow after connection details
• Domain extraction: Extract domains from tracker and Grafana ServiceInfo configurations
• Comprehensive testing: 5 unit tests covering various scenarios

Architecture

Follows the project's DDD/MVC patterns:

• View: src/presentation/views/commands/provision/dns_reminder.rs - Renders DNS reminder with warning icon, IP, and domain list
• Controller: src/presentation/controllers/provision/handler.rs - Orchestrates display after provisioning
• Application Layer: Reuses ServiceInfo from application layer for domain extraction

Behavior

The DNS reminder:

• ✅ Appears only when TLS domains are configured
• ✅ Lists all domains (tracker HTTP/API/health and Grafana)
• ✅ Shows the server IP address for DNS configuration
• ✅ Uses clear warning icon (⚠️) for visibility

Example Output

⏳ [1/3] Validating environment...
⏳   ✓ Environment name validated: lxd-local-https-example (took 0ms)
⏳ [2/3] Creating command handler...
⏳   ✓ Done (took 0ms)
⏳ [3/3] Provisioning infrastructure...
⏳   ✓ Infrastructure provisioned (took 26.1s)
✅ Environment 'lxd-local-https-example' provisioned successfully

Instance Connection Details:
  IP Address:        10.140.190.36
  SSH Port:          22
  SSH Private Key:   /home/josecelano/Documents/git/committer/me/github/torrust/torrust-tracker-deployer-agent-01/fixtures/testing_rsa
  SSH Username:      torrust

Connect using:
  ssh -i /home/josecelano/Documents/git/committer/me/github/torrust/torrust-tracker-deployer-agent-01/fixtures/testing_rsa torrust@10.140.190.36 -p 22

⚠️  DNS Setup Required:
  Your configuration uses custom domains. Remember to update your DNS records
  to point your domains to the server IP: 10.140.190.36

  Configured domains:
    - http.tracker.local
    - api.tracker.local
    - grafana.tracker.local
    - health.tracker.local

Testing

• ✅ 5 new unit tests (all passing)
• ✅ Pre-commit checks passed (linters, formatters, doc tests, E2E tests)
• ✅ Manual testing with HTTPS-enabled environment (positive case)
• ✅ Unit test coverage for UDP-only environment (negative case)

Acceptance Criteria

All criteria from the issue are met:

• Pre-commit checks pass
• Unit tests pass with comprehensive coverage
• E2E tests pass
• View follows MVC pattern with proper separation
• Uses UserOutput methods (not println!)
• Conditional display based on domain configuration
• Clear, actionable user guidance

[josecelano]

ACK b98450b