Now let's build something a bit more interactive - a counter contract! This is a classic example that demonstrates state management in smart contracts.
## Your Task
Create a counter contract that:
1. Stores a count value using `StorageU256`
2. Has a function to get the current count
3. Has a function to increment the count
4. Has a function to decrement the count
## Key Concepts
- `StorageU256` stores unsigned 256-bit integers
- Use `.get()` and `.set()` to read and write values
- The `U256` type from `alloy_primitives` represents big numbers