Fix malformed Close() method causing unreachable code

[sgaunet]

Problem

The Close() method in internal/app/client.go (lines 42-50) has incorrect indentation that causes unreachable code and potential logic errors.

Current code:

func (c *PostgreSQLClientImpl) Close() error {
	if c.db != nil {
		if err := c.db.Close(); err != nil {
		return fmt.Errorf("failed to close database: %w", err)
	}
	return nil
	}
	return nil
}

Issue: The inner if statement's closing brace is misaligned, causing:

• The outer function's return statements to be unreachable in some code paths
• Incorrect control flow logic
• Potential resource leaks if db.Close() errors are not properly handled

Expected Behavior

The method should properly close the database connection and return errors appropriately.

Proposed Fix

func (c *PostgreSQLClientImpl) Close() error {
	if c.db != nil {
		if err := c.db.Close(); err != nil {
			return fmt.Errorf("failed to close database: %w", err)
		}
	}
	return nil
}

Impact

• Severity: HIGH
• Type: Bug
• Location: internal/app/client.go:42-50

Checklist

• Fix indentation in Close() method
• Verify proper error handling
• Run unit tests to ensure no regression
• Check for similar malformed code patterns elsewhere