Fix/storage sol

[d1r1]

Refactor Storage System to Solidity-Compatible Layout

Summary

This PR completely refactors the storage system to provide a more ergonomic, type-safe API while maintaining full Solidity storage layout compatibility.

Key Changes

API Improvements

• Replace solidity_storage! macro with #[derive(Storage)] for better IDE support and Rust idioms
• Introduce strongly-typed storage primitives (StorageU256, StorageAddress, StorageMap, etc.)
• Add automatic storage packing for types smaller than 32 bytes
• Support composable storage structures through nested derives

Technical Enhancements

• Implement proper Solidity storage layout rules (slot allocation, packing, keccak256 hashing)
• Add native support for alloy types in storage codec
• Optimize storage access with direct slot manipulation for primitives
• Provide accessor methods for clean read/write operations

Migration Impact

• Updated all examples to use the new storage API
• Simplified ERC20 implementation demonstrating the new patterns
• Added comprehensive tests for storage layout verification

Breaking Changes

• Old solidity_storage! macro is deprecated
• Storage fields are now accessed through auto-generated accessor methods (e.g., self.balance_accessor())
• Storage types must use new Storage* wrappers

Example

// Before
solidity_storage! {
    mapping(Address => U256) Balance;
}

// After
#[derive(Storage)]
pub struct Contract<SDK> {
    sdk: SDK,
    balances: StorageMap<Address, StorageU256>,
}

// Usage
impl<SDK> Contract<SDK> {
    pub fn get_balance(&self, addr: Address) -> U256 {
        self.balances_accessor().entry(addr).get(&self.sdk)
    }
}