Support disabling some WASIp1 APIs

[rockwotj]

At the moment, the runtime unconditionally gives access to the filesystem, as well as all WASI APIs (system clock, etc). It would be good to make those options.

qjs/runtime.go

Lines 123 to 137 in 461716f

	if _, err := wsp1.Instantiate(option.Context, runtime.wrt); err != nil {
	return nil, fmt.Errorf("failed to instantiate WASI: %w", err)
	}
	if _, err := runtime.wrt.NewHostModuleBuilder("env").
	NewFunctionBuilder().
	WithFunc(option.ProxyFunction).
	Export("jsFunctionProxy").
	Instantiate(option.Context); err != nil {
	return nil, fmt.Errorf("failed to setup host module: %w", err)
	}
	fsConfig := wazero.
	NewFSConfig().
	WithDirMount(runtime.option.CWD, "/")

[mvp-joe]

It seems like a huge security issue to provide file-system access by default. I agree, seems like you would want that off by default and only enabled if someone opts in.