fix: check kill() input

[antongolub]

closes #1337

await assert.rejects(() => kill(''), /Invalid/)
await assert.rejects(() => kill('foo'), /Invalid/)
await assert.rejects(() => kill('100 foo'), /Invalid/)
await assert.rejects(() => kill(100.1), /Invalid/)
await assert.rejects(() => kill(null), /Invalid/)
await assert.rejects(() => kill({}), /Invalid/)

• Tests pass
• Appropriate changes to README are included in PR

[Copilot]

Pull Request Overview

This PR adds input validation to the kill() function to ensure it only accepts valid process IDs. The function now validates that the PID is a valid positive integer, rejecting empty strings, non-numeric values, floats, and other invalid inputs.

• Adds input validation to reject invalid PID formats
• Updates type signature to accept string numbers alongside numeric PIDs
• Includes comprehensive test coverage for various invalid input scenarios

Reviewed Changes

Copilot reviewed 5 out of 7 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
src/core.ts	Adds PID validation logic and updates function signature
src/log.ts	Updates LogEntry type to accept string number PIDs
test/core.test.js	Adds test cases for invalid PID validation
build/core.cjs	Compiled JavaScript output with validation logic
.size-limit.json	Updates bundle size limits to account for added validation code

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[Copilot]

The type assertion as \${number}`is misleading since the validation hasn't occurred yet. At this point,pid + ''` could be any string (e.g., 'null', 'undefined', '[object Object]'). Consider moving the type assertion after the validation or using a different approach.

Suggested change

	pid = (pid + '') as `${number}`
	if (!/^\d+$/.test(pid)) throw new Fail(`Invalid pid: ${pid}`)
	const pidStr = pid + '';
	if (!/^\d+$/.test(pidStr)) throw new Fail(`Invalid pid: ${pidStr}`);
	pid = pidStr as `${number}`;

[Copilot]

Pull Request Overview

Copilot reviewed 5 out of 7 changed files in this pull request and generated no new comments.

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