📝 Description

This PR introduces an opt-in strict parameter to the u8aToU8a function to prevent silently converting null or undefined inputs into empty Uint8Array instances.

💡 Motivation

While working with this function, we noticed that passing null or undefined was producing empty arrays instead of throwing errors, leading to hard-to-trace issues. This behavior caused 134 test failures. Instead of modifying every test and potentially introducing inconsistencies, we chose to add a strict checking mode.

🔧 Changes

• Adds a strict boolean parameter (default: false) to u8aToU8a.
• When strict is enabled, the function throws an error if the input is null or undefined.
• Default behavior is preserved to maintain backward compatibility.

✅ Benefits

This approach allows developers to opt into stricter input validation when needed, reducing the chances of subtle bugs or random runtime issues in downstream applications.

// Example usage
u8aToU8a(null); // Returns new Uint8Array()
u8aToU8a(undefined); // Returns new Uint8Array()

u8aToU8a(null, true); // Throws: 'u8aToU8a: Expected non-null, non-undefined value'
u8aToU8a(undefined, true); // Throws: 'u8aToU8a: Expected non-null, non-undefined value'