Test compilation of all STLC forms to VampIR

[rokopt]

Not all STLC forms yet have tests for compilation all the way to VampIR. I should add tests for all of them. This will depend on implementing at least

• Make use of VampIR modulus function to decompose products #57 , as well as fixing at least
• Missing type/object for left and right morphisms #53 .

I will also need to work out the status of

• Possibly-incorrect type error where Geb expects a product type #58 in the course of doing this.

[rokopt]

Can this be closed as fixed by the latest STLC fixes/enhancements such as #115 and #120 ?

[mariari]

no, see

https://anoma.github.io/geb/tests/cover-index.html

Namely https://anoma.github.io/geb/tests/436c3f34b05ce242465dc22105ccf7a3.html

shows that we don't have any tests that touch the snd logic.

we need higher test coverage and interpreter examples in general. I posted some recently but more should be had

[rokopt]

shows that we don't have any tests that touch the snd logic.

We should test at least this (snd), some projections, and some ill-typed cases. See the automated code coverage output.