Add format crate

[ferranbt]

Closes #91

[codspeed-hq]

Merging this PR will improve performance by 16.22%

⚠️ Different runtime environments detected

Some benchmarks with significant performance changes were compared across different runtime environments,
which may affect the accuracy of the results.

Open the report in CodSpeed to investigate

⚡ 2 improved benchmarks
✅ 72 untouched benchmarks

Performance Changes

	Benchmark	BASE	HEAD	Efficiency
⚡	interpreter/compile[rsi]	751.1 µs	640.6 µs	+17.26%
⚡	tokenize[complex]	74.4 µs	64.6 µs	+15.18%

Tip

Curious why this is faster? Comment @codspeedbot explain why this is faster on this PR, or directly use the CodSpeed MCP with your agent.

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_{Comparing feat-format (cbefdff) with main (095a842)}