Massive improvements

[paulmillr]

• Add support for EIP4844 transaction type from Dencun
• Transaction improvements
  • Improve transaction validation: now emits an array of errors for all fields
  • Stricter optional transaction validation: errors on technically correct, but bad values
  • raw property is now human-readable and easy to parse visually
• Add FetchProvider that consumes fetch built-in function and creates a Web3API-compatible interface
• Easy random key / address generation using addr.random()
• Add messenger to sign and verify messages by private key
• Remove dependency on RLP: use our own, on top of micro-packed
• Add 150MB of tests from ethers, viem, ethereum-tests and ethereumjs