Change port forwarding local port to 5433 and add operational commands documentation

[konokenj]

Summary

This PR updates the port forwarding configuration and adds documentation for operational commands output by CDK deployment.

Changes

1. Port forwarding local port: Changed from 5432 to 5433

   • Avoids conflicts with local Docker Compose PostgreSQL instances
   • Prevents accidental pushing of local changes to remote database

2. Documentation: Added a note in README.md describing the operational commands

   • Explains DatabasePortForwardCommand usage for local database connections
   • Mentions DatabaseSecretsCommand for retrieving credentials from AWS Secrets Manager

3. CDK snapshot tests: Updated snapshots to reflect the port change

Testing

• CDK snapshot tests updated and passing
• All changes verified locally

[tmokmss]

Thanks!