Provide a quick cast factory for users

[ProdigySim]

We should create a PojoMap.of() or a PojoMap.from() for casting map-like objects to PojoMaps quickly and safely. Many types can already be implicitly cast to PojoMap, so we should give people a way to do that cast without manually type asserting (with all of the generics...)

function of<K extends PropertyKey, V extends {}>(maplike: PojoMap<K, V>): PojoMap<K,V> {
    return maplike;
}

Examples

[ProdigySim]

This wouldn't help for casting from Record<string, T> to PojoMap<TinyType, T>, unfortunately.