Blue hydrogen with rigorous amine capture (multi-thermo)

The blue-hydrogen train done properly: steam-methane reforming and water-gas-shift run on a cubic gas EoS (Peng-Robinson), while the CO2 capture runs on the rigorous electrolyte amine package (MDEA/piperazine 'enrtl-mdea-pz') -- two thermo methods in one flowsheet, via per-node thermo_overrides. This is what legacy tools do with a property-method 'section' and what the plain 'blue-hydrogen-smr-ccs' showcase couldn't (one package per flowsheet forced a component-separator stand-in for the capture). Here the shifted syngas is contacted with a lean MDEA/PZ solvent in an absorber that removes the CO2 by real reactive equilibrium (H2/CO/CH4 pass through as insoluble gases), delivering ~94% H2 with the CO2 driven to trace and a rich amine at a realistic ~0.7 mol CO2/mol amine loading. Honesty notes: streams cross the PR<->eNRTL boundary carrying their universal fields (flow/T/P/composition), but each package uses its own enthalpy reference, so a rigorous energy balance across the boundary is not consistent (the absorber is a Kremser shortcut and doesn't attempt one) -- see the thermo_overrides note in docs/interfaces.py; the reforming/shift Keq are representative equilibrium magnitudes.