==============================================================================
POWER SIMULATION -- prev_f_full   [metric: success RATE]
==============================================================================
model: behavior ~ stim + day + stim:day + (1|rat)   (behavior = success RATE; day within-window)
observed groups: stim n=12, control n=12   nrep=120, alpha=0.05
ground truth: stim:day=+0.006292/day, rat SD=0.06824, residual SD=0.08152, days=10

 true stim:day interaction = +0.006292 (100% of observed)
  N/group  | per-animal power | LME power
  ------------------------------------------
  3        |  0.06            |  0.09
  5        |  0.17            |  0.16
  8        |  0.28            |  0.35
  12       |  0.37            |  0.41  <- observed
  16       |  0.55            |  0.62
  24       |  0.62            |  0.62

 true stim:day interaction = +0.003146 (50% of observed)
  N/group  | per-animal power | LME power
  ------------------------------------------
  3        |  0.03            |  0.04
  5        |  0.07            |  0.05
  8        |  0.12            |  0.15
  12       |  0.17            |  0.18  <- observed
  16       |  0.12            |  0.17
  24       |  0.15            |  0.13

Read the per-animal column as the honest power; LME is optimistic (obs-level DF).