Fix version mismatch error when dispatching encoded hints in storage compatibility mode (#2179)

### What is the issue

Fix version mismatch error when dispatching encoded hints in storage
compatibility mode

### What does this PR fix and why was it fixed

Remove version checks in HintMessage.Encoded serialization that
prevented dispatching hints written at storage compatibility version
(e.g., 12) when the peer connection uses a different messaging version
(e.g., 110).

UUID and VInt serialization are version-independent, and hint bytes are
written verbatim, so the version check was unnecessarily restrictive.

Author: driftx

src/java/org/apache/cassandra/hints/HintMessage.java

@@ -110,10 +110,11 @@ else if (obj instanceof Encoded)
             {
                 Encoded message = (Encoded) obj;
 
-                if (version != message.version)
-                    throw new IllegalArgumentException("serializedSize() called with non-matching version " + version +
-                                                       " for message with version " + message.version);
-
+                // UUID serialization is version-independent, VInt encoding is version-independent,
+                // and hint bytes are written verbatim. The size is the same regardless of the version
+                // passed, so we don't need to check for version mismatch here. This allows encoded
+                // hints written at the storage compatibility version to be dispatched correctly
+                // even when the peer is at a different (newer) messaging version.
                 long size = UUIDSerializer.serializer.serializedSize(message.hostId, version);
                 size += TypeSizes.sizeofUnsignedVInt(message.hint.remaining());
                 size += message.hint.remaining();
@@ -147,9 +148,11 @@ else if (obj instanceof Encoded)
             {
                 Encoded message = (Encoded) obj;
 
-                if (version != message.version)
-                    throw new IllegalArgumentException("serialize() called with non-matching version " + version);
-
+                // UUID serialization and VInt encoding are version-independent, and hint bytes are
+                // written verbatim (already encoded at message.version). This allows encoded hints
+                // written at the storage compatibility version to be dispatched correctly even when
+                // the peer is at a different (newer) messaging version. The receiver will deserialize
+                // the hint bytes using the appropriate version based on the hint file descriptor.
                 UUIDSerializer.serializer.serialize(message.hostId, out, version);
                 out.writeUnsignedVInt32(message.hint.remaining());
                 out.write(message.hint);