perf(parser): cleanup and optimize parsing jsx

[ulrichstark]

Removed what seems like unnecessary Context wrapping of parse_jsx_assignment_expression. Please double check on that, tests are at least still all green.

Also moved more common code into parse_jsx_fragment to shorten call sites.

[Copilot]

Pull Request Overview

This PR optimizes JSX parsing performance by eliminating unnecessary checkpoint/rewind operations and streamlining span construction. The changes focus on reducing parser overhead during JSX fragment and element parsing.

• Removes checkpoint/rewind mechanism when parsing JSX closing fragments/elements
• Eliminates the parse_jsx_assignment_expression wrapper function in favor of direct parse_expr() calls
• Optimizes span construction by avoiding intermediate span allocations and using direct calculations

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[codspeed-hq]

CodSpeed Instrumentation Performance Report

Merging #14234 will not alter performance

_{Comparing ulrichstark:cleanup-and-optimize-parsing-jsx (c18c0df) with main (1b0519c)}

Summary

✅ 37 untouched