E0106 — DimensionMismatch (compiler)

# Bug: Dense(512, 20) can't connect to LIF that was set up for 256 outputs
model = snn.Sequential(
    snn.Dense(700, 256),   # outputs 256
    snn.LIF(tau_mem=20.0, threshold=0.3),
    snn.Dense(512, 20),    # expects 512 but gets 256
    snn.LIF(tau_mem=20.0, threshold=0.3),
)

hidden_size = 512
model = snn.Sequential(
    snn.Dense(700, hidden_size),
    snn.LIF(tau_mem=20.0, threshold=0.3),
    snn.Dense(hidden_size, 20),
    snn.LIF(tau_mem=20.0, threshold=0.3),
)

E0106: layer dimension mismatch at layer 2
Why: layer 2 declares 512 input features but layer 1 produces 256 output features.
Fix: recheck the architecture — input/output sizes must chain correctly.
Docs: https://docs.thrindex.com/errors/E0106