WIP proxy support

[gr2m]

• implement TODO in code / remove timeout in test
• add test for post.js
• refactor to move child process logic into seperate library method, use method for both main.js and post.js
• Add standard tests that set NODE_USE_ENV_PROXY="1"

[Copilot]

Pull Request Overview

This PR adds proxy support by implementing child process spawning when proxy environment variables are detected but Node.js proxy support isn't explicitly enabled via NODE_USE_ENV_PROXY="1".

• Refactors main.js to wrap the existing logic in a run() function that checks for proxy configuration
• Adds proxy detection logic that spawns a child process with NODE_USE_ENV_PROXY="1" when needed
• Includes test cases and workflow updates to verify proxy functionality

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 3 comments.

File	Description
main.js	Wraps existing logic in async run() function with proxy detection and child process spawning
tests/main-spawns-sub-process-for-proxy.test.js	Adds test for proxy child process behavior (WIP with TODO items)
.github/workflows/test.yml	Updates workflow with proxy environment variables and adds dedicated proxy test job

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[Copilot]

[nitpick] The comment contains informal language. Consider updating to: // TODO: Mock not working as expected

Suggested change

	// TODO: why u not work
	// TODO: Mock not working as expected

[Copilot]

The exit code could be null when the child process is terminated by a signal. This should handle null values: child.on('exit', (code) => process.exit(code || 1));

Suggested change

	child.on("exit", (code) => process.exit(code));
	child.on("exit", (code) => process.exit(code ?? 1));

[Copilot]

This TODO indicates incomplete implementation that affects testability. Consider implementing the promise-based approach to properly support testing scenarios.

Suggested change

	child.on("exit", (code) => process.exit(code));
	// TODO: return promise that resolves once sub process exits (for testing)
	return;
	// Return a promise that resolves once sub process exits (for testing)
	return new Promise((resolve, reject) => {
	child.on("exit", (code) => {
	process.exit(code);
	resolve(code);
	});
	child.on("error", (err) => {
	reject(err);
	});
	});

[gr2m]

note to selves: current implementation in Node.js

https://github.com/nodejs/node/blob/4612c793cb9007a91cb3fd82afe518440473826e/lib/internal/process/pre_execution.js#L168-L187