Expose connection hooks

[dbousamra]

Summary

Connection hooks for dynamically resolving database credentials

Problem

Some workflows require dynamically resolving connection details (e.g. starting a local proxy and fetching credentials from a secrets manager) before a database connection can be established. The tool currently assumes static connection parameters, which makes these setups unsupported.

Proposed Solution

Add support for connection lifecycle hooks (pre-connect / on-connect) that allow running custom commands or scripts to dynamically supply host, port, username, and password at connection time.

Additional Context

Example use case:

• Start a local Cloud SQL proxy
• Fetch database credentials from a secrets manager

This pattern is common for cloud-managed databases and secrets-based auth.