perf: avoid cloning precompiles

[DaniPopes]

Precompiles::new().clone().into() would first clone the static default precompiles, then collect them into a new hashmap again in ContextPrecompiles. This shows up as about ~3% in Evm::transact profiles.

Avoid both cloning and collecting by using a CoW structure internally. This requires us to remove the Deref and DerefMut implementations as the internal type will be different depending on whether we have the default static precompiles, or a custom map. This should be fine as we can still support all necessary operations without exposing the underlying map type.

[rakita]

good idea!

Added few nit changes:

• Return Fatal error to not panic.
• PrecompileCow::Default renamed to PrecompileCow::StaticRef
• Return Boxed iter from addresses and additionaly added HashMap for addresses in Precompile.