Blueprints: Throw on failure

[adamziel]

Description

Ensures the Blueprint steps throw an error on failure. For now, the error is merely reported in the console. In the future, there may be a nice UI for this.

This PR is an addition to #605 as it prepares the Blueprint steps for the changes in the Blueprint compilation engine.

Detecting a runPHP failure required adjusting the php_wasm.c code to return the correct exit code. The previous method of inferring the exit code was replaced by simply returning EG(exit_status) which is populated by the zend engine.

Furthermore, this PR ships additional unit tests for some Blueprint steps to ensure they indeed throw as expected.

Changes description

throwOnError option

BasePHP.run() now accepts a throwOnError option that throws an error whenever PHP returns an exit code different than 0:

// This will throw a JavaScript exception 
await php.run({
	throwOnError: true,
	code: '<?php no_such_function()'
});

This happens in the following cases:

• syntax error
• undefined function call
• fatal error
• calling exit(1)
• uncaught PHP exception
• ...probably some more

This option is set to true by all the Blueprint steps.

Remaining work

• Rebuild all the PHP.wasm versions

Testing instructions

This PR comes with test coverage so confirm all the tests pass in CI.

Also, apply this PR locally and visit the following URL:

http://localhost:5400/website-server/#{%22steps%22:[{%22step%22:%22runPHP%22,%20%22code%22:%22%3C?php%20no_such_fn();%22}]}

It should reveal useful error information in the console.

[adamziel]

E2E failures come from #985. This PR merely surfaces the error that's already in there.