Combine Active/Reactive device constructors

Currently there's a number of device constructors that have reactive and non-reactive formulations where the reactive formulation is a strict superset of the non-reactive. I experimented in the past with making some helpers like _maybe_add_reactive... which unfortunately ended up in https://github.com/Sienna-Platform/PowerOperationsModels.jl/blob/main/src/common_models/network_conditional.jl which I would like removed ASAP.

I had Claude sketch a plan in https://github.com/Sienna-Platform/PowerOperationsModels.jl/tree/ac/reactive-refactor that I haven't examined closely yet. The important parts are:

on_reactive_power(f::F, ::NetworkModel{<:AbstractPowerModel}) where {F} = f()
on_reactive_power(::F, ::NetworkModel{<:AbstractActivePowerModel}) where {F} = nothing

and then for example

on_reactive_power(network_model) do
    add_variables!(container, ReactivePowerVariable, devices, D)
    add_to_expression!(
        container,
        ReactivePowerBalance,
        ReactivePowerVariable,
        devices,
        model,
        network_model,
    )
end

The diff is hard to tell right now, but looks like roughly ~1700 LOC removed and ~500 LOC added. My guess though is it slightly hurts precompilation time because now both branches have to be compiled?

Start by reviewing src/common_models/network_conditional.jl and the reactive-refactor plan linked in the issue, then inspect the affected active and reactive constructors. Consolidate the constructor paths without the obsolete helper approach, preserving behavior for both network-model variants and evaluating the possible precompilation impact.