ConstraintAnalysis: Add inequality parsing (#8891)

We now parse `i32.lt_s` and so forth.

This does not include full range analysis yet, so we don't infer
ties between `<=` and `<` for example, but this is already enough to
infer the precise inequalities we see, and their negations. This can handle
the simplest kinds of software bounds checks, more will be added later.

Also add proper printing of these opcodes.