#6 breakdown pt1 - add codegen

[yvesfracari]

original PR: #6

Added code generation capabilities

• Introduced web3_codegen in Makefile
• Updated codegen target to include Web3, orderbook, and subgraph codegen

Refactored project structure

• Removed contracts/ files (domain.py, order.py, sign.py)
• Eliminated order_book/ directory and contents
• Removed examples/ directory

Updated documentation

• Revised README.md for latest project structure
• Added note about signing orders in usage examples

Updated Chain enum for consistent explorer URL formatting

• Simplified imports in web3/provider.py
• Adjusted test suite, removing tests for refactored/removed components

[ribeirojose]

I wrote most of the commits here, so this is a bit weird 😆 but LGTM!

[gabrielfior]

I might be missing context, but I miss a bit of documentation here (in a README)

• How can one generate the autogen code
• Which package used
• When to update if needed

[ribeirojose]

I might be missing context, but I miss a bit of documentation here (in a README)

• How can one generate the autogen code
• Which package used
• When to update if needed

I added more instructions here. Lmk if that looks good and I'll go ahead and merge this =)