fix::added getMultiTableDefinition method (Issue #23)

[qmohitsingh]

Context:

• Issue https://github.com/agiletiger/ojotas/issues/23 outlines the need to do only one request to the DB to get all table definitions in codegen.ts

Proposed Changes:

• Implement logic to construct a single database query that retrieves all required table definitions.

What's Included:

• Introduction of getMultiTableDefinition: A new function that leverages the refactored getTableDefinition to fetch schema definitions for multiple tables in one go. This function is crucial for scenarios where schema information for several tables is needed simultaneously.
• Optimization in codegen.ts: The script now calls getMultiTableDefinition instead of making multiple calls to the older version of getTableDefinition. This change results in a significant reduction in database query count, especially in scenarios with numerous tables.

Technical Details:

• The getMultiTableDefinition function constructs a single SQL query that fetches column details (like column name, data type, and nullability) for all specified tables in a given schema.
• The results are then mapped to a structured format (MultiTableDefinition), making it easy to consume in other parts of the application.

Usage:

• The updated codegen.ts script will now call getMultiTableDefinition with the desired table names and schema, receiving a comprehensive map of table definitions in return. This single call replaces what would have previously been multiple calls to fetch each table's definition individually.

update:

• removed commented code
• set the return type of getTablesDefinition to Promise<Record<string, TableDefinition>>
• renamed the file to getTablesDefinition having a single method (remove the old one) with the same name
• put the values in the query, no need to send it in the other param as there is no safety risk

[qmohitsingh]

hey @nicoabie , could you please review this PR and let me know if this is what was expected or if any other adjustment needs to be made?

[qmohitsingh]

make sure to rename getTableDefinition to getTablesDefinition method and file before merging, great work

I will make that change, thank you!!!