Add DEFAULT keyword support for INSERT statements

Why it matters

This feature allows users to explicitly insert default values for specific columns in INSERT statements, improving flexibility and making it easier to handle columns with default expressions or values without specifying actual data.

How to use it

In an INSERT statement, use the DEFAULT keyword in the values list to insert a default value for one or more columns. For example:

INSERT INTO table_name (col1, col2, col3) VALUES (1, DEFAULT, 3);