feat: add strategy objects

[nbaztec]

What 💻

• Adds strategy implementations to Executor, Backend and CheatcodeInspector that allow overriding and extending functionality of these objects in the forks of foundry.
• Not all behaviors can be abstracted away as generic and therefore belong to Ext trait.
• The abstractions are not yet well defined. As a first step only those points are moved to strategy implementations where we had to made modifications in original code to work with zkEVM.

Why ✋

• Allows overriding behavior in the predefined strategy methods
• Allows easier modifications via swapping out standard strategy trait with extended strategy traits.

Evidence 📷

Tests pass

Notes 📝

• The base strategies are defined close to their usage in Executor, Backend and CheatcodeInspector.
• The EVM defaults have the original behavior preserved.
• The ZKsync strategy lives in its own crate. It wraps evm strategy within to work in cases where a fork is made to an EVM chain.