r2_nakagawa compatibility with HLCor object

[jbeauvais127]

Hello! Love your packages, but wondering if there is a way to make the r2_nakagawa function compatible with an HLCor object from the spaMM package? Seems like the get_variance function within "Insight" doesn't work with the structure returned by spaMM. Example code (taken from spaMM vignette) here:

data(scotlip)
lipfit <- fitme(cases~I(prop.ag/10)+adjacency(1|gridcode)
                +offset(log(expec)),
                data=scotlip,family=poisson(),adjMatrix=Nmatrix)
summary(lipfit)
r2_nakagawa(lipfit)

Warning message:
In get_variance.default(model, tolerance = tolerance, name_fun = "r2()", :
Objects of class HLCor are not supported.