Metaprogramming in Lean 4

Commits

• 06d8d3f: update Lean and mdgen (Seasawher) #131
• ad53e6f: fix typo in MetaM chapter (Seasawher) #131
• e2f2432: Erase errors in code examples in lean\main. (Seasawher) #131
• bc380f5: format code: trim whitespace, add annotation (Seasawher) #131
• 18ed517: import Std (Seasawher) #131
• cc108fa: erase errors in exercise 2/ch5 (Seasawher) #131
• 06f48bf: add description of #check_failure (Seasawher) #131
• 0b92cde: setup workflow to run CI (Seasawher) #131