Editorial hold: source material does not match topic

Held for sourcing. The reference material provided covers a Python output question, not Starlink, so publishing would have meant inventing the facts.

Linear algebra settles two of the three pressure definitions. The third needs a constitutive law, and the bulk-viscosity term shows exactly where the gap comes from.

Swap PV for the work integral and enthalpy stops being a state function. A two-path counterexample, the dH = TdS + VdP derivation, and the conditions under which ΔH really equals heat.