perf: rm RawSourceMap

[SyMind]

This PR removes the RawSourceMap intermediary to parse source maps directly from simd_json BorrowedValue for performance, and updates constructors and serialization accordingly.

• Replace RawSourceMap with direct parsing from &mut [u8] using simd_json::to_borrowed_value
• Update SourceMap::from_json/from_slice/from_reader signatures and implementations
• Switch serialization call (but introduced a potential misuse of simd_json::to_string)

[Copilot]

Pull Request Overview

This PR removes the RawSourceMap intermediary to parse source maps directly from simd_json BorrowedValue for performance, and updates constructors and serialization accordingly.

• Replace RawSourceMap + TryFrom with direct parsing from &mut [u8] using simd_json::to_borrowed_value
• Update SourceMap::from_json/from_slice/from_reader signatures and implementations
• Switch serialization call (but introduced a potential misuse of simd_json::to_string)

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 4 comments.

File	Description
src/source.rs	Removes RawSourceMap, adds direct JSON parsing using simd_json, updates constructors and serialization.
src/replace_source.rs	Updates test to pass a mutable byte buffer to SourceMap::from_slice.

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[codspeed-hq]

CodSpeed Performance Report

Merging #177 will improve performances by 37.78%

_{Comparing SyMind:refactor-simd-json (7ffc2c1) with main (d86a37a)}

Summary

⚡ 1 improvement
✅ 8 untouched
⏩ 1 skipped¹

Benchmarks breakdown

	Benchmark	BASE	HEAD	Change
⚡	parse_source_map_from_json	44.3 ms	32.2 ms	+37.78%

Footnotes

1. 1 benchmark was skipped, so the baseline result was used instead. If it was deleted from the codebase, click here and archive it to remove it from the performance reports. ↩