Aggregate demand from real consumers, do not fake it with a supply EMA

To make production/investment self-limit in an emergent economy sim, do not price against a demand reference that is an EMA of past supply — that expresses arbitrage convergence, not a demand curve, and normalizes any supply level back to base_value (no fixed point D(p*)=S). The fix is not to declare a demand curve (a forbidden knob) but to MEASURE the buyers already present: recipe inputs (each willing to pay up to the value its output unlocks) plus population needs, each a (WTP, quantity) pair. Clear supply against that histogram as a residual-supply auction: price = the marginal buyer reached. Self-limit capacity then scales with consumer count, emergently. Run decisions on knowledge.belief_price (learned, decaying) rather than the true price so actors can misjudge unscouted/glutted markets and correct via due diligence.