Rewrite interactive wizard with inquire for back navigation

Replace dialoguer with inquire crate for better navigation:
- 3-step wizard: Select Databases → Select Tables → Review
- Esc/Cancel goes to previous step instead of aborting
- State preserved when going back (database selections, exclusions)
- Simplified flow focused on core functionality

Users can now revise their selections without restarting the wizard.

Closes #8

Author: taariq