Let $D = \{a, b, c\}$ be a domain of discourse, and let $R$ and $S$ be two binary relations on $D$. A model $M$ is chosen uniformly at random from all possible models over $D$ (meaning for each pair $(x,y)$, the truth values of $R(x,y)$ and $S(x,y)$ are chosen independently with a probability of $\frac{1}{2}$ for True). What is the probability that the first-order sentence $\forall x \exists y (R(x,y) \lor S(y,x))$ is true in $M$?