The Run model used a strict Literal['baseline', 'explore', 'validate', 'wfv', 'oos']
for the phase field, but the new pipeline emits phases like 'phase1', 'phase2', etc.
This resulted in a silent validation failure inside the pipeline loop before MT5
was launched, causing the optimizer to appear 'stuck' without ever opening MT5.
Fixed by relaxing the phase field to 'str'.