V0.5🦊

Most of changes comes from here!

• statements are compiled once into Stmt objects
• expressions are parsed once and cached
• execution uses a dispatch table instead of repeated regex-heavy branching
• function bodies are compiled once too
• exec is still used only for ! Python blocks, because that feature is literally executing Python
• Fixed Bugs

And a concrete benchmark from this environment for the built in 10000 iteration test:

• time: 0.021500s
• peak memory: 0.00 MiB reported by tracemalloc for that tiny program

Added command's of:

python vulpin_opt.py app.vul

python vulpin_opt.py --selftest

python vulpin_opt.py --bench 10000