Plot per-channel diagnostic summary.
Shows posterior HDI width, mean spend correlation, saturation
gradient at current operating point, and posterior mean adstock
alpha for each channel.
- Parameters:
- colors
dict[str, str] | None Mapping of channel name to matplotlib color string.
Falls back to C0, C1, … when None.
- figsize
tuple[float, float] | None (width, height) for the figure. Defaults to
(10, 4).
- Returns:
tuple[Figure, ndarray of Axes]
