Attach source position to errors and propagate position info through query execution

[lovasoa]

Motivation

• Improve error messages by including the originating source file and span for SQL-related and arbitrary errors so users can locate problems in SQLPage sources.
• Ensure static-optimized statements and parameter binding errors carry source position information so error reporting is consistent during query execution.

Description

• Added a reusable helper write_source_position_info and refactored NiceDatabaseError::show_position_info to use it for consistent file/line output.
• Introduced NicePositionedError and the constructor display_stmt_error to wrap arbitrary anyhow::Error with a SourceSpan and source file for nicer display.
• Propagated statement positions through the pipeline by changing ParsedStatement::StaticSimpleSelect to include a query_position and updated parsing and matching sites accordingly.
• In execute_queries, map parameter binding and static-simple-select execution errors to include statement position using with_stmt_position, while preserving ErrorWithStatus semantics.
• Improved JSON error handling in sqlpage.link to return a clear anyhow! message for invalid parameters.
• Added unit test test_display_stmt_error_includes_file_and_line to verify the new positioned error formatting and adjusted existing tests to the updated StaticSimpleSelect variant.

Testing

• Ran cargo test which executed unit tests including test_display_stmt_error_includes_file_and_line and test_quote_source_with_highlight, and the SQL parsing tests updated for the StaticSimpleSelect shape; all tests passed.

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Codex Task