Feature: Add more data type support for key

### Feature description

this pg connector only support int type key for table for now , i don't see the reason, i think other type like varchar is possible, and it's common to use uuid or varchar as primary key

The issue names no files, tests, or entry points. Start by locating how the connector handles primary-key values and PostgreSQL column types, then inspect existing key-related tests. Done means tables using varchar or UUID primary keys are supported without breaking existing integer-key behavior.

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