feat: boxed simple ground literal extraction

[hargoniX]

This PR implements simple ground literal extraction for boxed scalar values.

[hargoniX]

!bench

[leanprover-radar]

Benchmark results for f88a5b9 against 9843794 are in! @hargoniX

• ✅ build//instructions: -837.8M (-0.01%)

Large changes (1🟥)

• 🟥 compiled/liasolver//instructions: +24.6M (+0.60%)

Small changes (5✅, 1🟥)

• 🟥 build/module/Lean.Compiler.LCNF.SimpleGroundExpr//instructions: +333.0M (+5.05%) (reduced significance based on *//lines)
• ✅ compiled/binarytrees.st//instructions: -7.9M (-0.01%)
• ✅ compiled/hashmap//instructions: -1.4M (-0.04%)
• ✅ compiled/qsort//instructions: -1.2M (-0.01%)
• ✅ size/compile/.out//bytes: -7MiB (-0.36%)
• ✅ size/libleanshared.so//bytes: -291kiB (-0.20%)

[hargoniX]

release CI is broken because of general CI issues, the interesting part here was fsanitize saying yes.