perf(lexer): faster decoding unicode escape sequences

[overlookmotel]

Tiny optimization to lexer.

Use peek_byte instead of peek_char, and move consuming { character in \u{ to directly after the peek_byte call, so that compiler can see that it's infallible and that the next char is definitely ASCII.

[overlookmotel]

• perf(codegen): faster printing quotes #10080 : 2 dependent PRs (#10046 , #10102 )
• refactor(codegen): print string literals containing lone surrogates without reference to raw #10044
• fix(parser): store lone surrogates as escape sequence #10041
• perf(lexer): faster decoding unicode escape sequences #10073 👈 (View in Graphite)
• refactor(lexer): shorten code for parsing hex digit #10072
• refactor(lexer): remove unnecessary line #10042
• refactor(lexer): clarify and reformat comments #10040
• refactor(lexer): simplify macros for string parsing + correct comment #10039
• fix(ast/estree): fix StringLiterals containing lone surrogates #10036
• main

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[codspeed-hq]

CodSpeed Instrumentation Performance Report

Merging #10073 will not alter performance

_{Comparing 03-27-perf_lexer_faster_decoding_unicode_escape_sequences (59b855f) with 03-27-refactor_lexer_shorten_code_for_parsing_hex_digit (630e189)}

Summary

✅ 30 untouched benchmarks
🆕 3 new benchmarks

Benchmarks breakdown

	Benchmark	BASE	HEAD	Change
🆕	linter[RadixUIAdoptionSection.jsx]	N/A	2.7 ms	N/A
🆕	linter[cal.com.tsx]	N/A	1.2 s	N/A
🆕	linter[checker.ts]	N/A	3 s	N/A

[Boshen]

Merge activity

• Mar 27, 5:01 AM EDT: The merge label '0-merge' was detected. This PR will be added to the Graphite merge queue once it meets the requirements.
• Mar 28, 12:24 AM EDT: Boshen added this pull request to the Graphite merge queue.
• Mar 28, 1:08 AM EDT: A user merged this pull request with the Graphite merge queue.