Development of the Official SQL Formatter

[xterao]

Enhance support for the following cases and release it as the official version:

• Support for the PostgreSQL dialect
  Improve handling of PostgreSQL-specific syntax and conventions.

• Support for nested conditional and loop directives
  Accurately format deeply nested if, elseif, else, and for structures within SQL templates.

• Support for bulk UPDATE syntax (already implemented)
  Confirm and maintain correct formatting for batch update patterns.

• Establish formatting rules for consecutive AND / OR clauses
  Define consistent line-breaking and indentation behavior for logical operator sequences in WHERE or ON clauses.

• Whitespace control before and after subgroups
  Fine-tune spacing rules around logical or visual groupings within SQL statements.

• Line break and indentation control for elements between block comments
  Ensure elements placed between /* ... */ comments are formatted cleanly with appropriate spacing and indentation.

This enhancement will provide consistent, dialect-aware, and highly readable SQL formatting suitable for production use.