Energy Management System

Second PD9140 and do double conversion into the battery/inverter.
Use one for low power, both for high power. And more solar for the hot days running the air for extended periods.

That or you will need a load shed device. But I am not sure you would be happy with it. Probably too clunky in the application of low power (12 amps).

Finding a 10 amp circuit breaker may be difficult.

You mean other than by turning things on and off? The only ones I know of that would actively control the demand work by automatically cycling things on and off as needed (excepting, of course, fancy inverters such as you used until quite recently). They're rather expensive and would take a good bit of wiring and work to get set up appropriately.

Ultimately the breaker protecting the outlet you're plugged into will limit the current that you can consume. You don't need anything else from a safety point of view. I'd probably just get some sort of an ammeter and keep an eye on that as needed. There are a good many suitable ones available from Amazon and Ebay and similar places for reasonable prices.

Mex's circuit breaker suggestion would work fine, too, but you'd want some means of bypassing it when you have more power available. Possibly wiring one up in an adapter dogbone would be the simplest and handiest way to accomplish that.

An auto-reset A.C. breaker.