Enhanced Data Retrieval: Implement Join Conditions

[ZaidMaslouhi]

Description:

This PR introduces join filters for dataui-nestjs-crud, empowering you with greater control over related data queries. Users can now specify WHERE conditions within the ON clause of joins, enabling the creation of more intricate and specific queries.

Key Improvements:

• Increased Flexibility: Craft complex queries by filtering related entities based on custom conditions.
• Enhanced Data Retrieval: Retrieve specific subsets of related data, improving efficiency and focus.

Implementation Details:

• Introduces a new 'ON' property to the QueryJoin interface within @dataui/crud-request.
• Leverages this property to specify 'ON' conditions for joins.
• Implements comprehensive unit and integration tests for guaranteed functionality.

Benefits:

• Simplifies querying related data with precise control.
• Enables more efficient and targeted data retrieval.
• This PR elevates dataui-nestjs-crud's capabilities by empowering you with flexible join filtering.

#38