PR#54 edits (set TxType for scenarios)

[zeroXbrock]

Removes duplications from PR #54.
Since we're setting tx_type in TestScenario, we don't need to specify the tx type param in FunctionCallDefinition or CreateDefinition. Instead, we just inject the type-specific params at runtime, and based on those, the signing wallet will figure out what the tx's type should be. This saves us a lot of redundant tx_type function params.
Also replaces generator::types::TxType with alloy's consensus::TxType.