Code clean up around TryWriteBigEndian/TryWriteLittleEndian

[EgorBo]

Contributes to #94941

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[xtqqczze]

I wonder whether we could refactor so that the primitive types have internal methods for the implementation, e.g.:

namespace System.Buffers.Binary
{
    public static partial class BinaryPrimitives
    {
        public static void WriteDoubleBigEndian(Span<byte> destination, double value) => value.WriteBigEndian(destination);
    }
}

namespace System
{
    public readonly struct Double
    {
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        internal void WriteBigEndian(Span<byte> destination)
        {
            if (BitConverter.IsLittleEndian)
            {
                long tmp = BinaryPrimitives.ReverseEndianness(BitConverter.DoubleToInt64Bits(m_value));
                MemoryMarshal.Write(destination, in tmp);
            }
            else
            {
                MemoryMarshal.Write(destination, in m_value);
            }
        }
    }
}

[EgorBo]

I wonder whether we could refactor so that the primitive types have internal methods for the implementation, e.g.:

Not sure this improves anything to be honest. The main motivation behind this change is to remove unsafe code (in this case, duplicated unsafe code).