feat: support position column in common sql query

[KKould]

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Summary

• fixes: Feature: support position column in common sql query #18771

Tests

• Unit Test
• Logic Test
• Benchmark Test
• No Test - Explain why

Type of change

• Bug Fix (non-breaking change which fixes an issue)
• New Feature (non-breaking change which adds functionality)
• Breaking Change (fix or feature that could cause existing functionality not to work as expected)
• Documentation Update
• Refactoring
• Performance Improvement
• Other (please describe):

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This change is 

[Copilot]

Pull request overview

This PR adds support for position-based column references (using $1, $2, etc. syntax) in common SQL queries such as subqueries, CTEs, and PIVOT operations. Previously, this syntax was only available for stage queries (file reads).

• Adds reset_result_column_positions() method to assign 1-based positions to query result columns
• Calls the reset method at the end of query binding to enable position-based references
• Adds comprehensive test coverage for the new feature

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
src/query/sql/src/planner/binder/bind_context.rs	Implements reset_result_column_positions() method to assign 1-based positions to columns in bind context
src/query/sql/src/planner/binder/bind_query/bind.rs	Calls reset_result_column_positions() after query binding to enable position-based column references
tests/sqllogictests/suites/query/select.test	Adds comprehensive tests for position-based column references in subqueries, CTEs, and PIVOT operations

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