chore: bench source map clone/parse/stringify

[SyMind]

This PR adds benchmarking for source map operations including parsing from JSON and cloning operations. It extracts source map-related constants and functions into a dedicated bench module to improve code organization.

Creates a new bench_source_map.rs module with benchmarks for source map parsing and cloning
Moves source map constants from main bench file to the new module
Adds the new benchmarks to the criterion benchmark group

[Copilot]

Pull Request Overview

This PR adds benchmarking for source map operations including parsing from JSON and cloning operations. It extracts source map-related constants and functions into a dedicated bench module to improve code organization.

• Creates a new bench_source_map.rs module with benchmarks for source map parsing and cloning
• Moves source map constants from main bench file to the new module
• Adds the new benchmarks to the criterion benchmark group

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 3 comments.

File	Description
benches/bench_source_map.rs	New module containing source map benchmarks for parsing and cloning operations
benches/bench.rs	Integrates new source map benchmarks and removes moved constants

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[codspeed-hq]

CodSpeed Performance Report

Merging #176 will not alter performance

_{Comparing SyMind:bench-raw-source-map (a77da66) with main (e1bd85d)}

Summary

✅ 7 untouched
🆕 3 new

Benchmarks breakdown

	Benchmark	BASE	HEAD	Change
🆕	parse_source_map_from_json	N/A	44.3 ms	N/A
🆕	source_map_clone	N/A	1.4 µs	N/A
🆕	stringify_source_map_to_json	N/A	16.7 ms	N/A