feat: add Quickfall IR layers

[Zffu]

The current IR of Quickfall is very rudimentary and is hard to implement anything into, this is why the entire Quickfall IR should be rewritten:

• HIR: AST but with resolved name, types and enforces that the code is working and valid
• MIR: Lowering of the HIR to go into a block instead of a tree structure. Doesn't contain high level structures such as loops
• LIR: Lowering of MIR to LLVM IR