Byte.fromHexString constructor

Creates a Byte from a hexadecimal string.

The hex string should contain pairs of hexadecimal digits (0-9, A-F). Spaces and common separators are ignored.

Example:

final data = Byte.fromHexString('48656C6C6F');     // 'Hello'
final spaced = Byte.fromHexString('48 65 6C 6C 6F'); // Same as above
final mixed = Byte.fromHexString('FF00AB');         // [-1, 0, -85]

Throws InvalidFormatException if the hex string is invalid.

A comprehensive wrapper class for byte operations, supporting both single bytes and byte collections.

This class provides Java-like functionality for working with 8-bit signed integers (-128 to 127) and collections of bytes. It can represent a single byte value or work with byte arrays, similar to Java's Byte class and byte[] arrays.

Key Features:

• Single byte operations: Wrap and manipulate individual byte values
• Byte array support: Work with collections of bytes (List<int>)
• Type conversions: Convert between signed/unsigned, different radixes
• Bitwise operations: Full support for bit manipulation
• Java compatibility: Method signatures and behavior match Java's Byte class

Usage Examples:

Single Byte Operations:

// Create single bytes
final b1 = Byte(127);                    // Maximum positive value
final b2 = Byte(-128);                   // Minimum negative value
final b3 = Byte.parseByte('42');         // Parse from string
final b4 = Byte.parseByte('FF', 16);     // Parse hex

// Basic operations
print(b1.value);                        // 127
print(b1.toUnsigned());                 // 127
print(b2.toUnsigned());                 // 128 (unsigned representation)
print(b1 + b2);                         // Byte(-1)

// Bitwise operations
final result = b1 & Byte(15);           // Bitwise AND
print(result.toBinaryString());         // Binary representation

Byte Array Operations:

// Create from byte arrays
final bytes = Byte.fromList([65, 66, 67]);        // From List<int>
final fromString = Byte.fromString('Hello');       // From string
final fromHex = Byte.fromHexString('48656C6C6F');  // From hex string

// Array operations
print(bytes.toList());                   // [65, 66, 67]
print(bytes.toString());                 // 'ABC'
print(bytes.toHexString());              // '414243'

// Manipulate arrays
bytes.append(68);                        // Add byte
bytes.appendAll([69, 70]);               // Add multiple bytes
final subBytes = bytes.subBytes(1, 3);   // Get substring

Advanced Operations:

// Validation and ranges
print(Byte.isValidByte(200));            // false (out of range)
print(Byte.isValidByte(-100));           // true

// Conversions
final unsigned = Byte.toUnsignedByte(200);  // Convert unsigned to signed
final signed = Byte.toSignedByte(200);      // Handle overflow

// Utility operations
final checksum = Byte.calculateChecksum([1, 2, 3, 4]);
final reversed = Byte.reverseBytes([1, 2, 3, 4]);