greedy_value_model

Greedy value model: annealed_assignment's value model with a greedy picker instead of the annealer. It exists so the ladder shows what the optimiser is worth on its own.

Idea: same energy terms, no search. Launch at the best-valued tracks one by one (skipping any track inside the blast radius of one already picked) up to the launch cap, whenever the net value is positive; fire the gun at the best net-valued track in range. build(), energy() and every knob are identical to annealed_assignment.py, and a test keeps them identical.

The annealed_assignment docstring describes the model in full.