[FEATURE] Interval analysis to improve a..b

[konnov]

Apalache translates the range operator a..b to SMT only if a and b are
constant expressions. This annoys the users: #425, #150.

The standard workaround is to find two constants c and d such that
c <= a /\ b <= d in all states. Then the user can rewrite the range operator
a..b as {i \in c..d: a <= i /\ i <= b}. This works in Apalache, as the
range c..d is constant.

We could do it better. By running interval analysis, we could automatically
compute c and d, if such constants exist. Moreover, the static
analyzer could give the user better feedback, as it does not have to be as
local as the SMT rewriter.