📝 Fix v4 upgrade guide output and code rendering

[taras]

Motivation

The v4 upgrade guide shows parent: end before child: end even though the child sleeps for 10 ms and the parent sleeps for 100 ms. Its code blocks also display literal { and } entities because an unclosed inline-code backtick causes the MDX preprocessor to escape braces inside subsequent examples.

Fixes #1259.

Approach

• Correct the final two lines of the v3 and v4 output examples.
• Explain that a child can resume while its parent is suspended, and change the prose's sleep(1) reference to the example's sleep(100).
• Close the Function.prototype.call() inline-code span so the examples render with literal braces.

Validation: ran the example against Effection 3.6.1 and 4.2.0; both outputs match the corrected guide. Reproduced the brace corruption before the edit, then verified that all 13 rendered code blocks match their source exactly after the edit. deno lint and git diff --check pass. deno fmt docs/upgrade.mdx reports no target files because Deno does not format .mdx files.

[pkg-pr-new]

Open in StackBlitz

npm i https://pkg.pr.new/effection@1260

commit: 69d2037

[codspeed]

Merging this PR will improve performance by 10.13%

⚡ 1 improved benchmark
✅ 5 untouched benchmarks

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
⚡	Memory	effection-inline.recursion	5.4 KB	4.9 KB	+10.13%

Tip

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

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_{Comparing codex/fix-v4-upgrade-guide (69d2037) with v4 (67bb5b4)}

[github-actions]

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Effection

Effection is a structured concurrency and effects framework for JavaScript.

Effection

Effection is a structured concurrency and effects framework for JavaScript.