vm2: NodeVM nesting guard accepts array-shaped require and permits host RCE

## Summary The `NodeVM` constructor computes `hasRealRequireConfig` using `typeof requireOpts === 'object' && requireOpts !== null`, so `require: []` bypasses the guard intended to reject `nesting` without an explicit require configuration. `makeResolverFromLegacyOptions()` then destructures the array to undefined option fields and returns a resolver containing only `NESTING_OVERRIDE.vm2`. Any attacker whose JavaScript is executed by a downstream `NodeVM` configured with `{nesting: true, require: []}` can load the host `vm2` module, create an inner `NodeVM` with an attacker-selected builtin allowlist, and execute commands as the host process. No equivalent plain-object validation exists in `makeResolverFromLegacyOptions()`. Array is converted into the vm2-only resolver: https://github.com/patriksimek/vm2/blob/54b54b74a382577f0bcd0538c5bf99acdcd7f53b/lib/resolver-compat.js#L205-L226 Nesting loader returns the host VM constructors: https://github.com/patriksimek/vm2/blob/54b54b74a382577f0bcd0538c5bf99acdcd7f53b/lib/nodevm.js#L640-L645 ## Proof of Concept Preconditions: - The host creates `NodeVM` with truthy `nesting` and array-shaped `require`. - The attacker can supply JavaScript executed by that `NodeVM`. ```javascript 'use strict'; const {NodeVM} = require('./index.js'); const outer = new NodeVM({nesting: true, require: []}); const result = outer.run(` const {NodeVM} = require('vm2'); const inner = new NodeVM({require: {builtin: ['child_process']}}); module.exports = inner.