CSHARP-5786: Add Decimal128 ctor overload for byte/short, for compatibility with net10 (#1819) (#1820)

(cherry picked from commit 1ef7fcc)

Co-authored-by: BorisDog <[email protected]>

Author: sanych-sun

src/MongoDB.Bson/ObjectModel/Decimal128.cs

@@ -1523,6 +1523,25 @@ public Decimal128(Half value)
         }
 #endif
 
+        /// <summary>
+        /// Initializes a new instance of the <see cref="Decimal128"/> struct.
+        /// </summary>
+        /// <param name="value">The value.</param>
+        [CLSCompliant(false)]
+        public Decimal128(sbyte value)
+        {
+            if (value >= 0)
+            {
+                _highBits = 0;
+                _lowBits = (ulong)value;
+            }
+            else
+            {
+                _highBits = Flags.SignBit;
+                _lowBits = value == sbyte.MinValue ? (ulong)sbyte.MaxValue + 1 : (ulong)-value;
+            }
+        }
+
         /// <summary>
         /// Initializes a new instance of the <see cref="Decimal128"/> struct.
         /// </summary>
@@ -1559,6 +1578,16 @@ public Decimal128(long value)
             }
         }
 
+        /// <summary>
+        /// Initializes a new instance of the <see cref="Decimal128"/> struct.
+        /// </summary>
+        /// <param name="value">The value.</param>
+        public Decimal128(byte value)
+        {
+            _highBits = 0;
+            _lowBits = value;
+        }
+
         /// <summary>
         /// Initializes a new instance of the <see cref="Decimal128"/> struct.
         /// </summary>