✨ Add support for CREATE and ALTER queries

[David-2357]

Add support for building and executing CREATE and ALTER queries through the query API.

At the moment, the library appears to focus on standard data manipulation queries, but it should also support schema definition and modification operations.

This issue proposes extending the query builder to allow generating and executing:

• CREATE TABLE
• CREATE INDEX
• ALTER TABLE
• ADD COLUMN
• MODIFY / CHANGE COLUMN
• DROP COLUMN
• ADD / DROP CONSTRAINT
• Other common schema-related operations

The goal is to provide a consistent and fluent API for schema queries, aligned with the existing query builder design.

This would improve the library by enabling developers to manage database schema changes directly through the same abstraction layer used for other queries.

Suggested considerations:

• Fluent and consistent API design
• SQL dialect compatibility across supported databases
• Safe handling of schema modifications
• Backward compatibility
• Full test coverage for generated SQL
• Clear documentation with examples